Right now, there is more free music available than ever before (free as in gratis, not as in fell off the back of a van). Artists and organizations that distribute music are making available individual tracks and often whole albums for download, and much of this free music is as good if not better than much of what is commercially released by traditional record labels.
As far as I have been able to ascertain, these media files are all legally and freely downloadable, at least for non-commercial use. Many are explicitly labelled with an appropriate
Creative Commons licence.