This is gonna be the thread where we talk about stuff

If you're able to fully credit the musician (in the credits or whatever) you could find someone who has released music under the Attribution Creative Commons license. Liiiiiike Kevin MacLeod: Incompetech.com. His is just an attribution license, not Attribution-Sharealike, so as long as you credit him you don't have to release your work under Creative Commons. There's a lot of stuff in there as background tracks for movies and etc. Maybe you'll find something good? I dunno. Good luck!