Find them on mapquest. Its out in a cornfield. Oh and the bridge is out one of the ways to get there, so you will have to take a few back roads to get there.
Review:
Eric the owner is a great guy. He is very helpful and doesn't charge anything to play there. However, he does accept donations to help with air and equipment (please give him some sort of donation).
I have played there 3 Sunday's in a row and there has been good competition almost every weekend. One of the days I was there, OSU, OU and a few guys from Miami of Ohio were there practicing. Which was great because they were all very friendly and were pretty fun to play with. I didn't care for the sideline coaching, but it was still pretty fun.
The field is set up in an X-ball style and provides lots of options for breakouts. There are a few bunkers that had blindspots... however I was told that they switch the field up pretty often there.
I highly recommend this field if you enjoy speedball. It is basically free to play there and the competition is better than most fields I have been to. The field is well kept and the turf is outstanding. I didn't use knee pads or anything the last time I played. It is very soft and the grass is thick and healthy.