Bogie's Mystery Tours® - The original participatory mystery events company!
Brilliance - Audiobooks company that produces the Amos Walker series on tape.
Overbooked - LOADS of great stuff for mystery fans.
ClueLass - A must-see site for mystery lovers!
The Gumshoe Site - All sorts of mystery-related news and links
The Mining Company - Fabulous information on authors, both contemporary and classic.
The Thrilling Detective - An extensive source of information on the hard-boiled genre
Western Writers of America - Estleman is a member, and former president.