Pike County was created on Feb 1, 1815 from Adams, Ross and Scioto Counties. If he last preached at Snodon Sarents on P P in 1797, it must have been in one of those counties. I'd contact their genealogical and historical societies.
In 1800 I don't think Foster Cemetery was located in Pike County; probably in Adams, Ross or Scioto Counties. Then Pike County was created in 1815. Successful Searching!