The Jonesborough Genealogical Society currently has 2 of the History of Washington County, TN 2001 ed. by Joyce and Gene Cox, they are $35.
We still have the Early Settlers of Washington County, TN: (pre) 1768-1777 book available for $90 as well as the Historic Washington County, TN Tour Booklet for $10.
Also, another Christmas gift idea for the genealogist/historian in your family is a membership in the JGS. Individual Membership is only $15 (Family Membership is $20, preferred by couples) and includes the Jonesborough Record Newsletter once a year, as well as events, tours, and other membership activities all-year long.