It really depends on what you want to read.
For something really scary - Salem's' lot is awesome, also "It" ( hate clowns so much)
For fantasy - The dark tower series is teh best. But it's quite long. "The talisman" is very good" and "The eyes of the dragon" is a relatively short book, which reads more like a fairy tale, dark fairy tale.
For something more mystical - Thinner is good
For Aliens'n'stuff - Tommyknockers scared me a lot when I read it for the first time( that I was 12 and with very rich imagination has nothing to do with it, I swear)
"The Stand" is also very interesting. And thought provoking...to bad there are no zombies there