Coscarelli's new film is based off of the cult horror/comedy book of the same name by David Wong. This is one of my favorite books being directed by the man who made one of my favorite movies (Bubba-Ho tep). You used to be able to read the entire book online, but the author got a lucrative publishing deal and took it down.
http://www.aintitcool.com/node/35692
Official website:
http://www.johndiesattheend.com/
While the novel isn't online anymore, here is a short story in the same vein of the book:
http://blog.myspace.com/index.cfm?fuseaction=blog.view&friendID=345870899&blogID=445396568