100 Killer Thrillers - The best books of suspense and adventure. This list was the result of votes by listeners of NPR in August, 2010.
Mystery Lists - A number of lists of "best mysteries" either selected by experts or award winning books. From the Booklist Center.
Haycraft's Detective Story Bookshelf - There are many classic mysteries on this list. If you have an ebook reader, many of the older ones may be found free on the web at sites such as Many Books