I have no idea whether musicfree.co.nr is legal or not.

I like We7 - free MP3 music download service laucned by music rock legend Peter Gabriel. We7 allows to download an MP3 song that is free, legal, safe and the artist gets rewarded! They add ad messages to the songs, but after a period of time (4 weeks) you will have the choice to have the MP3 song 'ad free'!