Mt. Doom is the only one that still runs walk on Sundays. If you were going to be able to play Saturday I would say http://www.pbnation.com/showthread.php?t=2932855
here, they do have airball up at all times. I have actually only been to Doom once, its a nice layout, but correct me if I am wrong, looks like it is a little more woodsball oriented, but they do have an airball setup.