There is one in Sioux Falls - right along the river/bike path at I-229 and Cliff. It is on the East side of Cliff Avenue and the south side of the river.
So, if you ever make it to "East River" that's where you can play!
Tuthill (mentioned above) in SF is pretty fun and challanging.Supposedly there is also one on the Southeast Tech campus too haven't played that one yet. Brookings has two that are pretty fun. Oakwood State Park (Northwest of Brookings) has a nice one too.