Start at MP3.com... Learn how to 'rip' cds to MP3s... then find a good FTP program, and learn how to use that... then teach your friends how to do it... and us IT to share your files...

Alternatively, once you've learned how to rip MP3s, get a gmail account (1 gig of space for free) and invite your friends to get accounts as well.. use those accounts to email MP3s back and forth...