I have several William Blacks in my family tree. Some of whom came from Mecklenburg, NC. "The Tunis Hood Family" book lists several.I do not see a specific listing for the ones you list here. Their history of the Black family of Mecklenburg really starts with John Black, born August 25, 1779 in Mecklenburg County, NC.He may be a cousin to your William.This book is available through Amazon books (it was last year anyway.)I think several other places also carry it.It has quite a bit about this particular line of the Black family. Hope this helps.