Nope, not in the slightest.

Sharing copyrighted material without permission ain't legal. However, there are a few pay-per-download systems from which copyrighted mp3s can be bought with the copyright holders permission, and there are of course lots of genuinely uncopyrighted mp3s available on P2P networks. I can't claim any great taste in music myself, but some of the genuinely free music is a lot better than some of the stuff churned out by the music industry.