Project Gutenberg, an online library containing free electronic texts of books whose copyrights have expired in the United States, includes some mystery and crime fiction. Browse the following sites:

Mystery Fiction Bookshelf. Works by Edgar Allan Poe, Wilkie Collins, Bram Stoker, and others.

Detective Fiction Bookshelf. Works by Sir Arthur Conan Doyle, G. K. Chesterton, Mary Roberts Rhinehart, Agatha Christie, and others.

Crime Fiction Bookshelf. Works by E. W. Hornung, Maurice Leblanc, Sax Rohmer, and others.

Mystery and crime fiction is published by scholarly and especially general trade presses. There are are also a number of  publishers and booksellers that specialize in mystery and crime fiction. Lists of these publishers and specialty bookstores can be found in the following sources.

Bookseller World. Includes guides to specialist dealers, auctions, information on book collecting, and more.

MysteryNet.com. Lists of retail mystery bookstores in the U.S. (by state), Canada, Europe, and Australia.

Sisters in Crime. An association of women writers and female characters in mysteries. The site has a list of mystery bookstores.

Writer's Market. annual. Belk Reference. Ref PN161 W83. Includes a book publishers subject index.

In addition to the many Internet sites listed throughout this guide, hard core mystery and crime fiction readers will want to check out Publishers Weekly, the weekly magazine of the publishing industry. Each issue contains reviews of forthcoming new hardcover and paperbound mysteries, and at least once a year, often in May, an issue focuses specifically on mystery and crime fiction new publications.