For me, my solution was to learn to do it myself, but your mileage may vary. I work in a free DAW called LMMS, and with VST plugins I've found on Woolyss. There's a lot of free resources out there for music creation, but ultimately if you want the best stuff you are eventually going to have to spend money (or pirate, I suppose).
Other than that, I agree with Rob. There's a ton of super cool dudes out there just trying to get their work in the public eye, and if you show them something impressive enough they might be willing to work with you on those grounds. If you're established enough and making good money, then commissioning artists may also go a long way.