Don't know anyone there personally, but a couple thoughts come to mind...
You may be able to find something by calling Cass County, as Real Estate records are Public Information. Maybe you'll get someone on a slow day....
Second thought: The Minnesota Historical Society may be able to help. My wife has used them in the past for some things, and they were really helpful, I guess.
Minnesota Historical Society homepage | Minnesota Historical Society
Good luck!
Jim
