I see three possible marriages for him in Jefferson County:
KING, JEFFERSON BUCK, NANCY 1835-10-15 002 0143 JEFFERSON
KING, JEFFERSON PAGE, MARY ANN 1845-04-18 002 0143 JEFFERSON
KING, JEFFERSON DAWSON, MARGARET 1863-02-23 002 0144 JEFFERSON
I don't see any land records for him in Jefferson or Franklin county when I searched the IL State Archives:
http://www.ilsos.gov/isa/landsrch.jspSandy (Whalen) Bauer