The State provided each county a Tract Book which contained names, land
description, and often the place of residence, when an individual entered the
land. Also, some libraries have the Land Office records on microfilm for
Indiana, except the land in the southeastern part of the state, called The
Gore, which was entered at the Cincinnati Land Office.
Here is an online site for land patents.
http://www.glorecords.blm.gov/
I didn't find a William Chambers, but just typing in the surname and Decatur
for the county, there was a James, John and Nicholas Chambers who were
patented land in Decatur Co. IN. Keep in mind the patent date is the date
the land was paid for. The Tract Book gives the date they entered the land
(put down a down payment). Also, the Tract Book may show land entries that
do not appear in the Land Patents, as a family might not have been able to
pay for the land or perhaps moved on. Since William Chambers appears to have
not received a patent, he may have purchased land from someone else and this
record would be in the a deed book.
Clear as mud? lol.
Good luck in your search.
Lou