I'm scared and I LIKE it

In late October, our thoughts naturally turn to the dark side.  Books like The Amityville Horror, Haunted Wisconsin, and The Salem Witch Trials Reader disappear from the non-fiction shelves.  It may not be for everyone, but there are many people who genuinely enjoy being scared.  To appease this "unnatural" reading appetite, here are a few books that may make you think twice about turning off the lights at night.
Old school or "classic" horror relies on building suspense instead of gore.  Take for example the author Ira Levin.  In Rosemary's Baby, The Stepford Wives, and The Boys From Brazil, the author depicts a normal world with average people in situations gone terribly wrong.  There is EVIL lurking just beneath the surface of their normality.  Books like Stephen King's Carrie with its realistic high school setting of a bullied, misfit girl versus her tormentors, Robert Harris' Hannibal Lecter series with its cannibalistic character, or Richard Matheson's I Am Legend resonate with the reader because there is a kernel of truth at the heart of the tale.  Who doesn't want their beloved family pet to come back to them as in Pet Sematary?  Doesn't being confined to the house and cut off from civilization during the winter months drive everyone a little nuts like in The Shining? 
Horror plays upon the natural or unnatural fears of the reader.  In The Exorcist, The Omen, and The Bad Seed, children are manipulated by evil or they are using evil to manipulate those around them.  Inside the reader the seed of doubt as to the actual innocence of those children is planted as their stories unfold.  Terrifying vampire stories have been around for decades thanks to books like Bram Stoker's Dracula and Anne Rice's Vampire Chronicles.  In those stories, a bite on the neck does not lead to undying love, it leads to unquenchable thirst for the blood of others or a painful death.  They love people only for their value as a food source. 

Don't have time to be scared to death by a book?  Nearly every one of the books mentioned have been made into a movie at least once.  Some of them, like Dracula, have been revamped and updated many times over.  They may not have an over-the-top "slasher" appeal but these are subtle stories that will wiggle down into your mind and make you think twice before you turn out the lights at night.