You can only add MP3 files as music to your page. MP3 file must be smaller than 5meg (5000kb)

Under My Profile select -> My Personal Files
*Upload your MP3 file here.
*Once its uploaded, copy the link to that file.

Go back to your profile page and edit it.
My Profile -> EDIT -> profile
*Scroll to bottom of the profile edit page and enter the URL to your mp3 file.

Save and thats it.

This info is not valid anymore, upload music under the audion section instead