Have you written to the county clerk for a copy of the death certificates?Some will have the location of burial on them.Another idea may be to locate the last known address and research close cemeteries to that address, using the lat and long of the location.Here is a link to help you:
According to the Illinois Statewide Marriage Index, George Nicholas married Lizzie A. Mercer in Stark Co., IL 26 May 1874.
He is found in the 1870 census, as follows:
Illinois, Stark, Toulon
Nicholas, George W. 26, Merchant, $14,500 RE, $7,000 PP OH
Nicholas, Hannah, 62, Keeping House $1,300 PP OH
Nicholas, Electa, 24, School Teacher, $800 PP IL
Nicholas, Sarah, 22 School Teacher, $800 PP IL
Illinois, Stark, Penn
Nicholas, George 50, Farmer, $2,000 RE, $550 PP VA
Nicholas, Hannah 50, OH
Nicholas, George W., 22 OH
Nicholas, Rebecca, 20 OH
Nicholas, Electa, 18 IL
Nicholas, Henry, 16 IL
Nicholas, Sarah, 12 IL
Illinois, Peoria, Not Stated
Nicholas, George 42, Farmer, $500 RE VA
Nicholas, Hannah 40, OH
Nicholas, Maria 16, OH
Nicholas, Isaac 14, OH
Nicholas, George 12, OH
Nicholas, Rebecca 11, OH
Nicholas, Electa 8, IL
Nicholas, Henry 6, IL
Nicholas, Sarah 3, IL
Maria married Allen Parrett in Stark Co. on 6 Apr 1858.
Isaac married Martha Humphrey in Stark Co. on 27 Sep 1858.
Rebecca married Ezra J. Griffin in Stark Co. on 25 Feb 1864.
Sarah married William H. Graves in Stark Co. on 8 Oct 1870.
Not sure about Henry...
There is a civil war record here with some personal identification info:
Interestingly, the military record indicates that George W. was married at the time he mustered in on 12 Aug 1862.When I checked, I couldn't locate a marriage record for him prior to his 1874 marriage so this could be an error.There is also a notation that he was a paroled prisoner.Hmmm...now that would be interesting to research!
I couldn't find any land records.
I hope you find this information helpful.I wish you the very best of luck with your continued research.