I think it is worth noting that Bret Easton Ellis has two books on the list, and honestly, Chuck Palahniuk could have several more. I remember going to a Barnes & Noble while I was traveling for work and picking up copies of American Psycho, Lullaby by Palahniuk, and then a Thomas the Train book that I bought for my nephew. The clerk looked at me like I was a serial killer.
Palahniuk, for what it's worth, does the best job of disturbing me. The story alluded to in the link, about the guy getting stuck at the bottom of a swimming pool, is one of the most unnerving things that I have ever seen put to paper.