University of St. Andrews (UK)
University of St. Andrews: Alan Turing
This site from the University of St. Andrews provides an extensive biography on Alan Turing details his childhood, education, accomplishments, invention of the Turing machine, and more.
Other
The Alan Turing Homepage
This site is dedicated to Alan Turing. It has a timeline of important events in his life as well as links to sites with additional information on him.