Last year I ran into Avalon Project at the Yale Law Library. This is repository of primary source historical documents ranging from, 500 B.C. to A.D. 2003, that are wonderful for your classically educated child to use as part of his history studies. Also the information is freely available, which is such an important quality to consider when homeschooling.
So if you are looking for primary source writings, or you just want to read The Laws of Hammurabi, The Statutes of William the Conqueror, or The Barbary Treaties, you are in for a treat.