I don't believe that Richland Co., actually recorded deaths prior to the 1900's.From what I have found, there are only a handful of deaths that were recorded at all.Most states did not even require them at all until after WW1!
Tracking the family back in time to Ohio would probably be your best chance of "pinning" Thomas to his family of origin.Considering that he lived in Geauga Co., OH during the 1830 and 1840 census years, you may want to research there a bit.Finding Lindley males (or females) in the state of Ohio that have children ages 1-10 in the 1810 census might help you narrow your search.Then searching through probate records in counties where the probable males reside might reveal a will that indicates Thomas as an heir.
You will also note that he was married twice.His first wife, Melinda was born in NY and is listed on the 1850 Stephenson Co., IL census with their children.By 1860, he is married to Barb who claims her place of birth as Pennsylvania.
I did scan the Illinois marriage database and did not locate a marriage for Barb and Thomas so I checked the Wisconsin database and found that Thomas L. Lindley married in Lafayette co., WI 9 Jul 1859.Note that Lafayette is only one county above Stephenson.
I am sorry that I could not be more assistance.I wish you the very best in your continued research.