Why don't you just torrent Adobe Audition? Or You could get adobe premier (via torrent) which is a pretty good program for editing animation/movies and making amvs. (It's what my boyfriend uses.) I think it might be easier to use because you can edit things on a frame by frame basis. Which I think may be more useful than Audition because audition is more for just audio.
Though I don't know. ^^;
Here is a tutorial:
How to Add, Delete and Rename Adobe Premiere Pro Video/Audio Tracks | eHow.com
In any case what program where you planning on doing this in?
Also what format is you anime in, mkv ect?