I'd suggest you try this setup...Waxwing all-you-can-eat luncheon.EF 300mm f4 IS lens at f5.6, EOS 7D camera at ISO 3200, 1/640 shutter speed, AV mode, +1/3 EC. AI Servo AF. Handheld, ambient light.
First, set your camera to only use "whole" ISOs... not the interprolated 1/3 stop ISOs in between the whole ISO stops, which are known to give lower image quality. In some of your images you are using ISO 250 and there is no reason to use such a low ISO with 7D (and particularly not a third stop such as this). There's a custom function (C.Fn I, 2... option 1) that sets the camera to only operate in full ISO increments (not C.Fn I, 1... which sets f-stop and shutter speed increments, leave those in 1/3 or the default 0). You'll have 100, 200, 400, 800, and even 1600 to work with very little concern. 3200 and 6400 can even be quite usable in some cases, shooting RAW and with some work in post-processing, perhaps. Try it and see what you think.
Using the first image (butterfly: Papillorama_0532) at you Flickr as an example...
If you had used f8 instead of f11, you would have gotten a bit more background blur and instead of 1/8 would have been able to use 1/15 shutter speed. Further, if you'd bumped up the ISO to 800, you would further have been able to increase shutter speed another one and two third stops, to 1/50. This shutter speed is probably workable with the 100L, maybe hand held, definitely on a tripod...
But you also need to leave IS on (there is no reason to turn it off, even on a tripod, with that particular lens.... it will turn itself off if not needed). Doing this, you would not have needed to use 2 second delay release. Just release the shutter with gentle pressure, not stabbing at it hard with your finger. IS will correct for any slight camera movement pretty well. (The only reason to use a 2 second delay would be if you were also using mirror lockup... which would have been a good idea at 1/8 shutter speed you used, but not so necessary if you used other settings to increase shutter speed to 1/50... mirror lockup is most important on 7D at shutter speeds between about 1 or 2 seconds and 1/15. Other cameras, with larger mirrors, might be important over a wider range of shutter speeds.)
If you'd gone to f5.6 with the aperture, you'd have been at 1/100 shutter speed. Even better if you want to hand hold, but now the depth of field might be getting a little shallower and more difficult to work with, depending upon how close you are to the subject. Teamspeed suggest using shutter speeds double your focal length (1/200) minimum for higher magnification shots and that's probably wise in many cases. However, yours is an IS lens and you should be able to handhold it around 1/100 with some practice. (But note that the closer you are, the higher the magnification, the harder it is to handhold and the less effective IS will be).
In that example of yours, though, you were very well situated with the subject parallel to the plane of focus, so might have gotten by just fine with a larger aperture and shallower depth of field.
You were using f11, and that might be good for macro shots if you have enough light and the small aperture doesn't cause your shutter speeds to be too slow. If shutter speed is getting too slow, then open up to f8, even f5.6... It's okay to use the 1/3 stops with the aperture or shutter, if necessary.
If the only flash you have is the built in one, I'd suggest don't use it for macro shots (actually I won't use it for much of anything.... well maybe in an emergency for fill for an outdoor portrait with a strongly backlit subject, but not much else... it's weak and in a terrible place for redeye and ugly shadows).
While I generally agree with turning off auto focus and using manual focus for macro shots, you need to learn a macro focusing technique.... What Teamspeed mentions. Instead of turning the focus ring on the lens, move the camera, lens and yourself closer to or farther from the subject to get it in focus. When doing this manual focus technique, it can help to select an AF point and set your camera to One Shot before you switch off AF, so you get Focus Confirmation (the "beep" and the green LED in the viewfinder). That can augment the accuracy of your manual focusing nicely.
And, as mentioned already, 7D offers another special focusing method with Canon macro lenses such as you have, that you might try too. In this case, leave AF on, set the camera to AI Servo, select a single AF point and keep that right on your subject, while half-pressing the shutter release continuously so that AI Servo continuously updates the point of focus. Take the shot when you see things snap into focus. There won't be any Focus Confirmation in AI Servo, though... you sort of have to trust the camera to achieve accurate focus. (FYI, personally I use Back Button Focus and find it more convenient than half-pressing the shutter release, separating focusing from the shutter release entirely. It's particularly useful when using AI Servo with moving subjects and you might want to try it sometime... Perhaps with easier subjects, slower moving first. In AI Servo you simply start focusing and maintain pressure on the button with your thumb as long as you want the camera to keep focusing... Taking shots by tripping the shutter release with your fore-finger any time and as often as you wish.)
Another trick you can use, whether focusing manually or using AF, on or off a tripod, is to take a burst of shots. Set your camera to 8 fps and fire off 3 or 4 or more shots... Likely one of them will be in focus. You can just throw away the bad ones. As you get better with practice you might need to do this less. But it's a handy trick to use when hand holding at low shutter speeds and when focus is tricky.
With macro shots, you will get fewer acceptible shots. So be patient with yourself and keep practicing. Get some books on macro photography and read about other techniques to get the shots you want. Macro photogrpahy is a huge subject... there are times to manual focus only, and even set One Shot so your camera will give you Focus Confirmation (the "beep" and the green LED) even while focusing manually. Other times, with other subjects, it's better to use standard AF and One Shot... or, with 7D and Canon macro lenses, the AI Servo auto focus method mentioned above.
Also choose your subjects carefully. Look for them in more brightly lit areas, so that you don't have to use flash. Use a reflector to "bounce" more light onto your subject. I've even worn a white shirt at times when shooting macro, because it will reflect light onto the subject. (You have to balance this sort of thing off against scaring away skittish subjects.)
Insects are more active during warmer times of the day... so early morning when it is cool and they are more sluggish can be a good time to go shoot. Often they look for a sunny spot to warm up, too, which can help you with better lighting.
You might have to wait for the sun to move and better illuminate your subject. There can be a lot of patience required, doing photography of any type! Ansel Adams would wait all day or even for several days to get one "perfect" shot of a scene he wanted to capture. Or return day after day or even months or years later when situations were more favorable.
Following are some examples, several I think I've posted here on POTN before...
Each year in late January or early February when food is scarce waxwings come in large flocks to several trees near me, to dine on the berries... They are hungry enough to tolerate me getting fairly close to get some shots of the activitiy... The first year I was lucky and got some shots I was happy with, over a couple days shooting sessions... The next year I was expecting and watching for them... Ready when they arrived, and able to make a number of additional shots over a few days....
For this shot, I kept pushed the ISO pretty high to have a fast shutter speed, because the birds are very fast moving around and gobbling down berry after berry. Ultimately, over the course of two seasons, I got about a dozen or 2 dozen shots I'm really happy with. I didn't know I'd caught the above bird in mid-gulp, until I was looking at the images later. This was the only shot from any of my shooting sessions both years, where the bird's tongue can be seen. I have some others that are good, too, where they have berries in their beak and/or some other nice poses, shots of a pair of birds, etc.
This week the waxwings have suddenly shown up early and are chowing down at these trees while there are still leaves on them. I'm thinking of trying to get some shots, but the birds may not be as hungry and seem much more wary of me. If I want to get some shots with the green leaves still on the trees, I'll have to try another technique... Such as using my car for a blind, parking it near a tree and waiting inside.
Hummingbirds are a popular macro or semi-macro subject that take some patience and planning... But can be attracted with feeders and acclimated to allow people to get fairly close. Still, they are tiny, very fast and fleeting... so bring your patience. Anna's hummingbird (F) at feeder.EF 500mm f4 IS lens with 1.4X II teleconverter at f5.6. EOS 10D camera at ISO 200, 1/200 shutter speed. 550EX flash with Flash Xtender used for fill (Av mode), no compensation. Gitzo 1325 tripod, Kirk BH-1 ballhead, Wimberley Sidekick.
I maintained several humingbird feeders in my yard for years, conveniently located near a patio where I can sit and relax with a cup of coffee (or whatever!) while waiting for the birds to show up for a snack. Normally I'd use a higher shutter speed with a hummingbird in flight, you can't hope to start freeze their wing movement with less than about 1/640 or faster. However, using a flash in this case, I knew that it would help freeze the motion. A flash acts like a shutter speed of about 1/720, typically. There's a tiny bit of flash "ghosting" and subject motion blur in the above image... But I like that and the movement it implies, prrefer this over other images that froze the bird's movement more completely.
Be patient and practice. It takes time to learn various techniques to get good macro shots. The image below was made with a vintage lens adapted for use on one of my 7Ds... handheld, manually focused, and even manual aperture settings. The subject was in full sun, so no flash was needed. But the bee was moving quickly from flower to flower and around inside each flower. I probably took about 75 photos to get a half dozen or fewer that were in focus acceptibly, and of those only a few were nice compositions and "poses". Bee on orange poppy.Tamron SP 90mm f2.5 lens at f7.1, with 25mm macro extension tube. EOS 7D at ISO 400, 1/400 shutter speed, manual settings, manual focus, handheld, available light.
The vintage macro lens is difficult to use, the viewfinder gets quite dim when it's stopped down to give enough depth of field and Focus Confirmation quits working much past f8... But it's a very compact lens that fits into the corner of my camera bag easily. Nice when I want a macro lens, just in case, but am mostly planning other types of shooting.
Do get a flash when you get a chance... I really like the Canon MT-24EX Macro Twinlite (which I use with a custom flash bracket arrangement). It's good for macro shots up to and a little beyond 1:1 magnification. But it's a bit bulky, fairly expensive, and pretty specialized for macro use. (Note: I don't care for ring light flashses, such as the Canon MR-14EX, until shooting really high magnifications such as 2:1 or more. They give too flat lighting for my tastes, at lower magnifications. That's fine for some types of macro shooting... such as shots of coins and stamps or dental or scientific purposes. But for critters and flowers and such, I prefer to see more shadow modeling and "drama", than a ring light flash tends to give at lower magnifications.)
It doesn't have to be a macro-specific flash. For example, following was done with a Canon 550EX on an off-camera shoe cord, with a couple layers of white gauze over the flash tube to reduce it's output and diffuse it slightly, handheld off to the left and above the subject. I might of been using a monopod, but seem to recall I didn't have one handy so was balancing the camera and lens on top of an empty, upside down 5-gallon paint bucket. Hey! Whatever works! "I'm ready for my close-up, Mr. DeVille."Canon EF 100mm f2.8 USM lens at f11, EOS 30D camera at ISO 200, 1/200 shutter speed. Canon 550EX flash diffused and with off-camera-shoe cord. M mode, eTTL flash exposure, no flash compensation. Handheld (camera and lens resting on a support).
Mainly I'm showing the above image because I used a standard, diffused flash, rather than a macro-specific flash. I don't recall for certain, but I think I took about 30 to 50 shots to get the one above. This image also shows an effect of using full
flash as opposed to fill
flash. To get full flash, just set your Canon to M mode and it does full flash automatically... If wanting to use shutter speeds higher than 1/250 (on 7D, 1/200 or 1/300 on other Canons) you also need to set the flash to High Speed Sync. Notice the dark background in this shot... That's one effect of full flash, because the flash is the primary source of illumination and is stronger than the ambient light. You can try to balance flash with ambient light, still in M mode... Or set the camera to Av or Tv auto modes, in which case the flash will act as fill, rather than full. The camera will automatically expose for ambient light, and use the flash as a secondary source. You can dial the flash strength up or down, too.
Keep practicing, studying, trying things, reading and learning about macro photography. Don't be afraid to take a dozen or a hundred shots of a subject if you need to, to get one or a few good ones. (Try to not disturb the subject, though.) Macro is fun, but does require some patience and practice. Even with years of experience, all of us still have a lot of throw away shots... so don't worry too much about that.
PS... You might be having trouble adding images to your posts because you are relatively new here on POTN. I'm not certain it's the case here, but many forums restrict posting images until you have some number of posts... usually about ten. There are some tricks to linking to Flickr images, too.