[abbycomix]

I recommend Uzumaki for really disturbing and odd concepts and gore. It's about a small town cursed by spirals. VERY twisted and frightening imagery. They also made a movie of that one. And Pet Shop of Horrors which is slightly campier and more spooky than gross.
Also Parasite is pretty freaky and scary too.
I think Viz and Tokyo Pop put those trade paper backs out so you should be able to find them in bookstores and comic shops.