Check out these links for info on Central Ohio trails.

www.dot.state.oh.us/bike/Central03.htm (Columbus area)
www.dot.state.oh.us/bike/Southwest03.htm (Dayton, Xenia, Yellow Springs)

www.home.earthlink.net/~bikeohio/
www.statetrails.com/

I'm in Dayton, so I only familiar with that area, but Ohio is a beautiful place to ride the trails!