The earliest federal KY census that I have seen is for 1810. There are two books available that are called "The First Census of Kentucky" (1790) and "The Second Census of Kentucky" (1800), but they are really compiled from tax lists or military lists. There is also a book called "The Cornstalk Militia of Kentucky" which is a listing of able-bodied men in 1790 and 1791. Look for these books at any large library. In lieu of census, you should look for early tax lists. While they don't list, or even tally, the number of family members, at least they do list head of household. The ones for Madison County are available at the LDS library. (You can borrow the film at any branch library.) They are also available at the Allen County Library in Fort Wayne, IN.