I am a huge fan of music blogs. They are frequently updated treasure troves of all sorts of free music. These are my good ones of the moment, maybe you have some too?
http://dereksdaily45.blogspot.com/A new motown single almost every day! 1960s girl groups, Ike and Tina, Little Richard.. I am in heaven. I love this shit.
http://discodust.blogspot.com/Discodust is the reason my running playlist exists. All of my really good (meaning bad) remixes and new favorite djs have come from this blog
http://www.iheartcomix.com/Not as good as discodust, but still worth mentioning.
http://www.saidthegramophone.comFor those of you who aren't into motown or techno, here's THE indie music blog of the past five years or so. I found this site in high school and because of it was able to dazzle my friends with my musical taste (before they found it themselves). I've gotten so much good stuff from here, and it's varied. They even have a wikipedia, lol -
http://en.wikipedia.org/wiki/Said_the_Gramophone