aresgalaxy.org is a p2p program similar to kazaa without the spyware. Bitorrent is always good (remember not to upload RIAA music you wouldn't want a lawsuit) You don't get viruses from .mp3 files you get viruses usually by .exe files or stuff like that, watch out for files labled like .mp3.exe that would be bad. My favorite alternative to iTunes music store is
http://www.allofmp3.com its only $0.01 per megabite so songs cost $0.04-$0.10 verses the 99 cents you pay a song at itunes and you get to choose how you would like your music encoded! And yes iPods support mp3 format, songs you get from iTunes are in AAC formate and filled with DRM crap. I think iPods are overated expecailly considering there price and limit of functions.