The ironworks was called Neabsco and was located in Prince William County. Within the Tayloe Family Papers at the Virginia Historical Society you may be particularly interested in the annual slave inventories that the family compiled each year between the early 1800s and the 1830s (and beyond, although that's where my research stopped). These inventories list, for most farms and most years, the names, occupations, ages, and values of enslaved peoples. I conducted research on the Tayloe family and their various business operations (including the use of slave labor) for my dissertation at William and Mary, although my focus was on Virginia, not the Alabama operations begun in the 19th century.