I'm pretty new to recording, so I'm deciding to try it out. However, I'm not sure what sort of software/equipment/other things are necessary. I heard about audacity in some other threads, so right now I guess I'm gonna try to use that (put a mic in front of my amp and record like that). Does anybody have any other ideas?
Well, obviously what mic you use plays a large part. Also experiment with where you place it (ie don't just stick it in the middle, move it around and see what sounds best).

An audio interface to get sound into your pc is almost certainly necessary, because pc soundcards are complete crap. You can get cheap enough interfaces that do the job fine.

For software, if you just want hit-record-and-play software, Audacity's grand. For guitar-orientated fx and amp sims, take a look at Guitar Rig, ReValver, or Pod Farm. For full-on studio-style mixing, Reaper's your man.
Okay, checked out the line 6 stuff, they look pretty good, but I'm short on money right now so I'll just have to go with what I have, mic + Audacity. Thanks for the suggestions.