We accidently found one of those at Pole Mtn., WY. I knew about the beacons, but not the arrows on the ground. In fact, I didn't know what it was when we were standing on it and only learned about it later on some guy's blog site.
There's one near Rodeo, NM and the radio shack has been moved and turned into a cottage at a local motor court. It's the second airfield on this site:
http://www.airfields-freeman.com/NM/Airfields_NM_SW.htm#rodeoBTW, abandoned airfields would also be a fun to search for. My wife and I, since we are both pilots and worked for the airlines (as Dispatchers), also search for VORs wherever we go:
http://en.wikipedia.org/wiki/VHF_omnidirectional_rangeHappy hunting!
LS