Web: Fantasy author Terry Prachett's Discworld series has spanned over 30 years of books and short stories, and there's no way for a newbie to know where to jump in and start. Luckily, All Timelines is a web service that will tell you, along with guides for virtually every other pop culture franchise.
The user-contributed site covers books, comic books, TV series, movies and video games. The objective is to find any franchise's canonical chronology, or the official timeline of events in that fictitious world. Based on its canon, All Timelines lists every book, movie, video game or TV series that is officially a part of the franchise.
The site tries to keep things objective. For example, to catch up on Star Wars, most fans recommend the release order of the movies, and not the canonical order. But All Timelines is all about canon, and is an exhaustive resource worth checking out.