Paul,
I thought you and the researchers for Virginia should know that there is a free database online for the 1790 - 1800 Virginia Tax Lists. I have used it in the past but not recently, and it does have many Free People of Color on the lists. It features actual images and indexes, with a searchable database. The link is below:

http://homepages.rootsweb.com/~ysbinns/vataxlists/index.htm

Some other websites with Virginia Tax Lists are:

(Grayson County, VA - a transcribed Index)
http://www.ls.net/~newriver/va/gray1800.htm

(I Dream of Genealogy, features free links to tax lists for Brunswick, Buckingham, and Lunenburg Counties - early 1700's - early 1800's)

http://www.idreamof.com/tax/va.html

Deloris