An indexed resource on how to make your mystery fiction more realistic. (Published under my other name Anne Klarner)
Barnes & Noble.com
Writers Digest Books
You have a character that suddenly needs to turn blue and keel over. With Deadly Doses, you can look up in the symptoms index to find out which poisons do just that, assuming, of course that they work.
Don't turn off your mystery audience by giving your characters spasms from arsenic, when that's not what arsenic does.