Jane,
 
In the time it took me to read your list of sites with
African-American contexts in Virginia, I could easily think of 20 or
30 more. I will try to find the time to work on a list, but you
should know that the vast majority of archaeology done here, as
elsewhere, is contract work. The place to look for most of the data
you are interested in might be in the archives of the Department of
Historic Resources, as well as in the libraries of the major Virginia
research centers (VCU, William and Mary, and Colonial Williamsburg).
Take a look at Trish Sanford's recent review in William and Mary
Quarterly, which is a beginning, but only a beginning. Good luck,
 
Dan Mouer