I have lots of favorite music sites all with legal Indie music for downloading:
http://www.mp3.com (CNET's very own)
There are actually many more Indie music sites as well as many Indie podcasts that distribute free music continually. So, there are plenty of sites to get great music from independent artists.
Everyone seems to think that the Big 5 record labels that make up the RIAA are the only source for 'great' music. The fact is, the Big 5 labels, even though they have a lot of backing money, are really producing some of the worst musical content in their entire history. This is part of the reason bands/artists like NIN, Madonna, Radiohead, Prince and others are wanting to split from their labels and do it themselves. The taint that is the Big 5 is really having a negative effect on the bigger artists. So, these issues are dragging these artists names down with the label. Yes, these companies do have money, but money doesn't help when these companies are continually blundering and making stupid mistakes (like suing the very customers on which they depend).
With Indie artist sites above, these are artists who choose to deliver directly to the consumer under their own terms. Better, with unsigned Indie artists, there is no danger of a RIAA lawsuit ever. Almost all of the music is fully available for streaming. Many of the tracks are also available for download as MP3. Some of the sites even offer the ability to sell/buy music.
AcidPlanet, is a Sony owned company. This site primarily supports Sony's Acid Music products. However, they encourage remixing of commercial songs through contests on the site. They drop raw samples and let people use the Acid Music software to create their own mix and arrangement. Although, as an artist, you can also upload original works on AcidPlanet and distribute music there.
BTW, I also write music and distribute it among many of the above sites myself, so I am quite familiar with most of the sites and how they operate. You can listen at http://www.broadjam.com/abigguitar
Online music - Stores, streaming, discovery, social. Got a favorite? (For legal music we mean) chime in. Got questions? Ask 'em here.