No wonder it's confusing with the old counties: Mecklenburg County [North Carolina] was formed in 1763 and included the present-day North Carolina counties of Mecklenburg, Cabarrus, Union, Lincoln, Gaston, Rutherford, and Polk (and other western counties not yet settled at that time) and all or part of the South Carolina counties of Spartanburg, Cherokee, Union, Chester, York, and Lancaster. Fortunately, most or perhaps all of the Mecklenburg County wills survive. There's still hope for old John Dover's will :-) Appleton's Bookstore in Charlotte, North Carolina seems to have a wide selection of genealogy books: http://www.appletons.com/genealogy/homepage.html