Have you checked the Index to Ohio Wills to 1850? The Ohio counties changed quite often. I might be able to find something for you. My family was from Fayette County, PA and moved to central Ohio. I have done a lot of research there, but not for Alexander. I think the 1800 or 1810 Census for Fayette County is enumerated under Washington County. It's been a while since I have looked at that.