If you're interested in TOS music, there's a wealth of discussion of it in this thread
about the recently released box set containing literally all
the music from TOS. Or if you're interested enough to invest $225 plus shipping, you can buy the set
yourself and read its extensive notes.
Like my multi-bboard pal Ssosmcin, I'm as much a film music fan as a STAR TREK fan, and I bought the box set. It's a big investment, strictly for those of us who really love the episode scores. But if that's you, you'll get a lot of enjoyment out of it.