If you do weddings down the road then a couple of wireless mics might be a nice thing to have. Running those into a stand alone recorder like a DR-40 or DR-100 would give you some great sound up moments for both the cerimony and the reception. I suggest at least the Senheiser G2 or G3 mics. They are fairly small, light weight and nice quality for the money. Yeah they cost more than other cheaper options, but they will last you a long time and you'll get better sound.
Another option you could go with is a pair of H1s with lav mics attached and use them as small, personal recorders kind of like a wireless unit. Syncing up the sound later in post is all that's needed.
Then having a external mic like one of the Rode Videomics would be a great thing. That way you could have 3 different sources of sound to mix into your projects.
The problem with sound gear is that to get really good quality sound like what you hear on TV shows or commercials you have to spend a lot of money. Quality costs money. Starting small and working your way up to more gear is probably the best way to go as you are just learning and probably don't have a huge budget for sound gear right now.