Sherlockian.Net - Pretty good site. Claims to have everything the Web offers about Sherlock Holmes.
Sherlock Holmes online - This is the Official web site of the Sir Arthur Conan Doyle Literary Estate. It includes a specially written biography of Sir Arthur Conan Doyle and you can find information on his books and the films which were inspired by his writing.
The Arthur Conan Doyle Society -
Holmes on Screen - Your source for information about Sherlock Holmes in films and on television. There are also writings about Holmes, original fiction and more.