Trailer score

Hey,

So I am currently working on the trailer for my first proper film (doc) and after spending many hours searching the internet for an appropriate soundtrack for the trailer, have not had the exact result I am after...

Obviously, I want to do this legally.

The trailer will only be aired online.

I have a couple of friends who may be able to help me with a score, but this is not definite. So I was wondering if anyone else knows of any resources where I could find trailer scores/music...?

I found a couple of websites, but they weren't very comprehensive, and their quality was questionable...

Thanks in advance....