Not much there, but it lists a marriage for a Thomas Newlon: Sarah STROTHER, b. ca 1773 Fauquier Co VA, d. bef 1832, m. (1) Henry Powell 1787 Harrison Co VA, and (2) Thomas Newlon. I've seen another researcher with Thomas Newlon and wife Sarah Powell (Single Lineage Researcher Page "N"http://www.rootsweb.com/~lineage/00n.htm)http://www.rootsweb.com/~lineage/00n.htm). Thomas is listed having been born in 1780 in PA and died 1814 in Harrison Co, W VA.
There is also a reference to a John Newlon in Harrison Co, W VA: William (Lake, Jr.) was Justice of Peace in Harrison County, West Virginia in certified deed to John Newlon, on April 3,1824.
Hope any of this helps your search for Thomas' wife.