It seems appropriate to revive a horror thread.
I love horror movies and books, but very few actually scare me. The scariest thing I ever read was a single scene from Gerald's Game. The book was one of his weaker ones, but there's a scene involving an ear-ring on the floor that made me uneasy in a way few things do.
Netflix is turning Gerald's Game into a movie. I'm curious to see how they do.
Besides King and Straub, I'd also recommend Bentley Little. He can be hit or miss and some of his work has a satiric edge that may not make it 'horror', but he's not a schlock writer. I'd recommend The Ignored and The Summoning (neither yet available as e-book) or
The Store. Not as good as the other two, but there's an e-version available.