addink on 28/2/2010 at 20:31
(
http://www.soundsnap.com/)
is cheap (it used to be free, but alas), has a huge, easily browsable catalog and previews are of relative high quality and full length.
The quality varies but there are some gems in there.
Schattentänzer on 8/3/2010 at 09:53
I recently did something for GameStop. The guy who needed it just went to the forum most relevant to the kind of music he wanted (quick google I guess), said what he wanted, and got a lot offers within a few hours.
My advice would be to do the same, because generally people are eager to get their music out, especially if they want to have a career in that sector. Offer an appropriate fee you're willing to pay for one year non-exclusive use or similar. Chances are you'll get responses even if you can't pay anything.
