I don't know of any airparks around here, but there are quite a few building opportunities, both rural and suburb, within a mile or two of Bolton Field (KTZR), home of two RV-6s and a number of other homebuilts.
There is are 25 acres w/house, hangar, and grass strip for sell in Plain City for $1.4M. The flyer states that there are 30 more acres available. Sounds like a great opportunity to start an airpark.
If there was a developer wanting to start one in the Columbus area, I would move there in a minute.
