Their graves are listed on the Starke Co. site under findagrave. They were just listed today, 15 Dec 2012.
Denton William Leasure b. 03 Feb 1824 d. 27 Nov 1883;
Nancy Ann Watts Leasure b. Apr 1831 d. 28 Apr 1883.
No pics of grave there, but there's someone who will take a pic for you. (Round Lake Cemetery)