Just in case you haven't got this one already:
[ame=http://www.youtube.com/watch?v=Xhvd9twPEIo]YouTube - Conan The Barbarian(Suite) - Basil Poledouris[/ame]
(Actually, it's a special arrangement of all the major Conan tracks, and I don't know where it's available individually.)
I've always wanted to use this Tool song as background music for a battle with a god -- slow build to grandiosity -- but the lyrics that make it so awesome kinda get in the way. And amazingly, it's a tribute song to the artist's late mother.
[ame=http://www.youtube.com/watch?v=G-0rLI6-skQ]YouTube - Tool - 10 000 days (pt 2)[/ame]
I'd suggest tracking the Homeworld soundtrack online (or was it Homeworld 2). It has a lot of vaguely Middle Eastern music.