How do I put a song on my email address so that when I check my mail I can hear a song that I like?

Depending on the program you use to read your email, you should be able to change the 'new mail' sound, by checking the preferences, or settings. I'm not sure if you can play a whole song this way, but you can record a few seconds of the song and use that (save it as a .wav file usually works) as the 'alert' or whatnot.