But if you want something more "professional", then you can't beat this offer from MOBY-
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hi,
i've recently started a website called www.mobygratis.com
it's pretty simple.
it's a website that provides free music for independent and non-profit filmmakers.
there's no catch.
if you're an independent or non-profit film/video maker you can go there and download free, pre-licensed music for your film/video.
see, i was a film student at suny purchase(back when they offered an experimental film major), and ever since i've had a lot of friends in the world of indie film. and their biggest complaint is that it's hard/onerous/expensive to try and license music for low budget(or no budget)films.
so that's why i started mobygratis.com.
free music for indie filmmakers.
i hope that you find it helpful.
thanks
moby