Found Warren Co. VA Land Deed Book D255, probated 3 Sep 1849, John I. Johnston was living in Alleghany Co. VA. His wife was still living in Clarke Co. VA.
1850 census index for said county list a John T. Johnston (sic). At the moment the image on L.D.S. will not come up. I will check later to see if I can see who was living with him.
Listing of slaves shows he possessed nine slave in 1850. Not listed for that location 1860.
It would appear he was charged with murder but not found guilty. His family unit, however by 1860 census was living in the said various places and I have not found him.
The L.D.S. library has wills and death records for rent, will try those two films at a later date.