Some that come to mind - the mysteries of Jessica Fletcher, "Bad Twin", which was worked into the plotline of 'Lost', guide-books and diaries from 'Twin Peaks'. And there's one from a current soap opera, but I'm blanking on the show. And with over 400 books here in the Toobworld Central Library, it's a daunting task to track it down.
But now comes word that ABC will be publishing a mystery novel "written" by Richard Castle, the main character on its returning series 'Castle' and played by Nathan Fillion. Apparently elements of the novel will find themselves integrated into episode storylines.
Before the novel is published as a hard-cover, the first half of the book will be serialized online, a chapter a week for ten weeks. Its actual publication release date is September 29, by Hyperion.
The novel is "Heat Wave", so the protagonist must be Nikki Heat. She's a new character for Castle, having dispatched his previous hero Derek Storm after becoming bored with writing about him. Nikki Heat is influenced by the detective at the 12th Precinct who's been saddled with him by a veiled demand by the Mayor while she's working cases.
Since 'Castle' has a black man currently as Mayor of New York City, the show had to be relegated to an alternate TV dimension, as Mayor Mike Bloomberg has already established himself as "Hizzoner" in '30 Rock', 'Law & Order', and a Muppets Christmas special.
But I think it fits nicely into the dimension of 'The West Wing', the next best thing to the main Toobworld!