Notes From the Constitutional Convention
The Avalon Project, supported and hosted by Yale Law School, is a rich source for electronic copies of historical documents.
Avalon includes electronic versions of all of Madison's published notes from the Constitutional Convention. Rather than reinvent the wheel and convert these important documents to this website's conventions, links are instead supplied to provide direct access to the documents. Other pages of interest might be the Convention Timeline and the Convention Topic Page. Also relevant is Delegate Demographics and Sketches of the Delegates.
Main page for Madison's Notes. Note that the whole convention did not meet on Sundays.
Avalon also has notes from other convention attendees, though none are as complete as Madison's.