Look it up. It is fantastic. It is a wonderful piece of software. You can change the mood at exactly the points in time that you want, you can add hits, and more! It's like having a custom scorer in house...almost.
If you just want a bit more regular music library, you can try Digital Juice. Some of their collections are decent.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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I've had very good luck with Pond5. They have an immense number of tracks, but since it's a multimedia site, it's a bit tough to search in the normal way you would on a music site (by style, instrumentation, etc.). But there are loads of very good (and bad) tracks there.