This online journal publishes genealogical information about Prince William County - there are a number of articles with slave records, Freedman's Bureau papers, etc.

Worth looking at if you have ancestors from not only Prince William but Fauquier and Loudoun as well.

An inex of the contents is located at:
http://www.pwcgov.org/docLibrary/PDF/004493.pdf

Denise

"Prince William Reliquary

The Ruth E. Lloyd Information Center (RELIC) located at the Bull Run Regional Library publishes a journal featuring in-depth historical and genealogical articles related to Prince William County quarterly. Current and past issues of Reliquary can be found on our web site."