The Haunting of Hill House by Shirley Jackson
Kind of a post-modern Gothic novel-- a short book which is nevertheless thick with atmospheric suspense, mystery, and terror. And the ending... well, the ending is the best ending to a haunted house story ever.
Blood and Chocolate by Annette Curtis Klause
Old school paranormal romance, and a great paranormal romance at best. The book is quite different from the better-known movie... I like the book much better, but the books are always better, aren't they?
Dracula by Bram Stoker
I first read the horror classic Dracula at a very young age (10? 11?) and for some reason liked it even though I hardly understood most of the gruesome happenings. I've reread it four or five times since, and really enjoy the language and the suspense-- the Count is a vampire to which most modern literary vampires pale in contrast, in my opinion.
Thinner by Stephen King
One of the lesser-known Stephen King books... it possesses its own unique brand of horror, as well as a Gypsy Curse. Can't go wrong there.
Tokyo: Pet Shop of Horrors by Matsuri Akino
An older manga series which I really enjoy-- these are short stories about a magical, mysterious pet shop whose animal wares always seem to be perfect fits for their buyers...until the seemingly innocent pets turn out to be mythological creatures or otherwise supernatural beings.
Pretty Monsters by Kelly Link
This is a really great YA short story collection-- quite a few of the tales are creepy, but all of them are hilarious.
The Legend of Sleepy Hollow by Washington Irving
Really classic American Gothic. These are a million movie adaptations today (my favorite is the one with Johnny Depp-- differs from the book, but sooo good), but you can't beat the original creepy tale.
Anno Dracula by Kim Newman
This one was recently re-released after having been out of print for a while-- yay! Kind of a messy Victorian/steampunk-esque retelling of the end of Dracula, with side-appearances by Jack the Ripper. Read my review.
Sunshine by Robin McKinley
An older vampire book written in a more literary style than most vamp books today. It's recently been re-released with a YA-esque cover-- I like this one best, because it's the one I have and kinda creepy.
Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch by Terry Pratchett & Neil Gaiman
Hardly horror at all, but definitely supernatural... wonderfully apocalyptic, which I realize is an oxymoron. The combined writing powers of Neil Gaiman and Terry Pratchett resulted in this gloriously hilarious book a couple decades ago.
I'd love to know what you think of these classic/ slightly obscure books, and be sure to leave the links to your Top Ten in the comments section-- I always visit back and love to check out all the lists.