Land records can be a great way to locate your ancestor as they traveled across the US seeking better opportunities and freedom. The Federal government gave away or sold land at a discount to encourage settlement and commerce, especially in newly acquired territories such as the Louisiana Purchase. You can search for your ancestor on-line at https://glorecords.blm.gov/search/default.aspx.
You can search by name, location, and other criteria to try to find your ancestor. Once you do, you can download a copy of the actual land patent signed by the president! See a pdf of my ancestor, George Hunter in Knox County, Ohio. It was signed by president Andrew Jackson! You can learn more about land records in chapter 12 of my book, Find Your Roots Now!