There was a combined nearly $39 million of farms, ranches, hunting land and other land for sale in Madison County recently on Land.com. The total acreage of all Madison County farms and ranches for sale was around 3,000 acres. Madison County ranks 40th in the state for the combined amount of land currently advertised for sale. Of all ranches, farms, hunting land and other rural land and acreage for sale in Madison County, Rexburg had the most land for sale. Madison County is Idaho's 42nd biggest county (473 square miles). It's located in the Eastern Idaho region of the state.