Peter,

There are no books out there on Oklahoma. I have been watching and collection Oklahoma for about 10 years now. I would not say I have the best collection but I do have on the best 25.00 and below online collections. See link below. I will pick up a new set of chips from a casino this week that is not listed in the chip guide. I do have references on prices but have not had time to put it together but maybe when I retire this fall I can get around to it.

http://rubescasinochips.com/collection-casino-chips-tokens/oklahoma-chips-tokens-casino/

Paul S.
R-7745