Posted mine on this site and was suprised how many hits I had, probably at least 20 calls and turned down 5 offers. Was very lucky in that it got dismanrled and reserected 60 miles to the west. Nice to see the family barn live on. I couldn't justify the money it took to fix it up.
Definately make up a contract with not liable clause, and get proof of insurance. In OH everyone wanted the beams.

http://www.oldbarnwoodsite.com/old_barns_for_sale_.htm