You need to post the files somewhere on the web or on an FTP server and provide a link to them. Peferably a place where you can link to the song directly instead of making people register at a service like soundclick or whatever.

ie, $10 a month can easily get you about 5GB of space, you upload all your tunes to their server and provide direct links like this..

http://s93744050.onlinehome.us/mp3/Rocksplosion.mp3

You're probably better off posting MP3 files too, cause some of us Mac users have problems with .wmv files.