In the late 1970s, writer/editor/bookstore owner Otto Penzler edited a fascinating anthology. It consisted of short articles about 26 fictional detectives, written by their creators, the authors who invented the characters. It has been out of print for quite a while; I still have a much-thumbed-over Penguin paperback copy on my bookshelves.
Now, it's back. The Mysterious Press has published electronic editions of "The Great Detectives: The World's Most Celebrated Sleuths Unmasked by Their Authors" - and it deserves a place in the library of every reader of classic detective stories. Some names will be very familiar: there's an article about Roderick Alleyn by Ngaio Marsh, one on John Appleby from Michael Innes, an article on Inspector Cockrill from Christianna Brand. You'll find other detectives, like H. R. F. Keating's Inspector Ghote, Ed McBain talks about the 87th precinct, and Carolyn Keene looks at the origins of Nancy Drew.
You may not recognize some of them - Duncan Maclain, Quiller, Inspector Schmidt. There's even a classic cartoon character - chester Gould's Dick Tracy. The articles are all short and loaded with details from the authors about their brainchildren.
It's all available in a wide variety of electronic formats from Open Road Media and The Mysterious Press. The illustrated button on top will take you to Amazon for their Kindle version; if you are so inclined, I get a small percentage when you order from them through that link. If you prefer another format, you'll find a listing of the available versions by clicking here. Classic mystery lovers will really be doing themselves a feature by getting this book.