Here are some great places to start your research on Arthur Conan Doyle.
Also, don’t forget about World Book Student, linked on the right side of this page.
Websites:
http://www.arthurconandoyle.com/ Official site of the Sir Arthur Conan Doyle Estate
http://www.biography.com/people/arthur-conan-doyle-9278600 Biography from the bio.com website
http://sherlockholmes.stanford.edu/biography.html Biography from Stanford University
http://www.biographyonline.net/writers/arthur-conan-doyle.html Biographical information from Biography Online
http://www.sherlock-holmes.org.uk/conan-doyle/ The Sherlock Holmes Society of London
http://www.conandoyleinfo.com/ Biographical Info from ConanDoyleInfo
http://www.conandoyleestate.com/ Conan Doyle Estate biographical information