Honestly, I think a realtor would be your best bet to get good, solid information. Even if you could find the avg. price per acre, it might be misleading. Cheap land is usually cheap for a reason- it's not fertile, it doesn't have improvements, it's severely rural. Price per acre will depend on the type of land (home site, pasture, field, wooded area), whether it has improvements such as electric to the site, a well (or even possibility of a well), a driveway, etc. Also, the size of the parcel is something to take into consideration. I've seen 50 acres and 2 acres listed for the same price, in the same county. If the majority of land that is sold in your county is unimproved, raw land sold in parcels of 100 acres, and you're looking for a 5 acre parcel with a homesite and a well, the average is going to be misleading.