Well, I shoot Raw and use Lightroom, which can be (and is for many of us) a pretty much all-in one workflow app for our normal photography. I do my processing and normally start with exporting Web-size jpegs for my Web host. Then, if I do decide to print, I can print most of what I'd ever need on one of my two inkjet photo printers. So for that there is no need for routine sharpening other than the bit of "output sharpening" available in the Print module. I don't typically see the need for more than just the "standard" sharpening amount.
For some shooting, though, special sharpening techniques are really good. Portraits is one common "branch" where special tools are called for.
I'm not a portrait shooter, but I do wildlife/bird shooting, often in dim light, often shooting subjects that are small enough and/or distant enough that I never have enough reach, meaning that a close crop of a low light/high ISO shot is needed.
In those cases, the ability to "selectively sharpen" is great, especially when you are going to print at any size that will show up the noise, such as an 8x10.
But the good news is that Lightroom and I believe Aperture as well as the Camera Raw processor built into Photoshop have "local adjustment brushes" for selective sharpening/"softening".
As to what is best before exporting to the Web as compared to prepraring to print, well, I don't know if there is a cut-and-dry rule in regards to sharpening, although many people will output sharpening after resizing for the Web or, if needed, resizing for a print.
But yeah, if I'm going to go through a print lab/shop, I'd export a Web-size image as well as a print-size image. The Web jpeg goes into a Web "archive" on my external drive for future reference/availability, the print one would go into a dedicated folder that could then be burned onto a disk/saved to a card/USB drive/whatever.
