Let's celebrate with some links.

Sherlock Holmes Online: the Doyle estate's official website.
Arthur Conan Doyle Society: organization devoted to Doyle (and, apparently, at odds with the folks above).
Discovering Arthur Conan Doyle: Stanford University's "community reading project."
Friends of the Arthur Conan Doyle Collection: support for the Toronto Reference Library's special holdings in books, MSS, and other items relating to Doyle and Holmes. 
Conan Doyle Manuscripts: what they are and where they're to be found. 
New York Times obituary: reprint of the 1930 obit. 
Sherlockian.net: probably the ultimate guide to all things Holmesian.
221B Baker Street: e-texts, illustrations, etc.
The Diogenes Club: links and many e-texts, including J. M. Barrie's "The Adventure of the Two Collaborators."
Doyle Hyper-Concordance: search the Holmes stories.
Universal Sherlock Holmes: massive bibliography.
The Exploits of Brigadier Gerard: e-text of one of Doyle's historical novels.
The Adventures of Gerard: the same character.
The White Company: probably Doyle's most famous historical novel.
Charles Doyle: devoted to the work of Doyle's father, a painter and illustrator. 
Gaslight: small collection of parodies, including one by Bret Harte.
Sherlock Holmes Pastiches: "a listing of historical, fictional and canonical characters appearing, or mentioned in published Sherlock Holmes pastiches, parodies and other Sherlockian writings."
Sherlockian Pastiches & Parodies: includes Doyle's own "How Watson Learned the Trick."