MiscellaneousDiablo Archive is a collection of 4 of these books, but it doesn't appear to be in Diablo history chronological order.
<product no longer available>
was released in conjunction with Diablo 3, but since it isn't a novel, I'm including it here in the miscellaneous section. The book presents itself as an actual book from the Diablo universe. It has tie-ins to Diablo 3 though, so it should be ready towards the end of your Diablo reading order. Be sure to play the original games Diablo Battlechest [New Version], which Blizzard still supports. The newest game is Diablo III - PC/Mac. EDIT: Guide updated October 2012.