The value of farms and ranches for sale in Putnam County recently on Land.com was around $3 million. This represents nearly 1,000 acres of land for sale in Putnam County. Putnam County ranks 84th in the Buckeye State for the total acreage of land currently advertised for sale. Of all locations in Putnam County with land and rural real estate for sale, Continental had the most land for sale. Manufacturing and related services are the largest economic sectors in Putnam County. Putnam County is the 36th biggest county (484 square miles) in Ohio. It's located in the Northwest Ohio region of Ohio.