You'd aboslutlly love some of Frank Zappas avent garde work.
His first ever live tv performance was with a bicycle, but actually very creepy.
Zappa has great creepy stuff peppered inbetween the crazy experimental compositions that he would make.
Look into Arnold Franz Walter Schoenberg and his 12 tone system as well.
another instrument used to create horror movie soundtracks is the waterphone.
I'm a music nerd, so this post gets a 10/10 from me.