Other Galileo links
The Galileo Project at Rice University is full of useful links and information.
The Galileo room at the Museum of Science in Florence can be visited online.
The complete (Italian) text of Galileo's writings, including his correspondence, is available to see. Enter galileo opere in the search box: you will be presented with the opportunity to see any of the editions of Galileo's collected works, beginning with the 17th century ones.
An unpublished early manuscript, De Motu, is available online in a new translation by Prof. Raymond Fredette. This work has long been recognized as a key to Galileo's earliest thoughts on the question of motion, and therefore of great interest.
Aristotle's Physics and On the Heavens are available online.