I would like to say, Flickr music is the best free music/movies download library that exist today. Membership is very reasonable, they provide fresh tracks each month and they're more than happy to work with you and help you Set it up on your PC. Unlike other free Music download companies, Flickr music gives you the freedom to re-arrange the music tracks and use them in any way you want. What more could you ask for?
http://www.flickrmusic.com is the way to go .
Also try
http://www.kazaa-platinum.com