Curdog, I've called a few in my life. The big cats are about as stealthy as anything on earth, Seeing one in the wild is a rare occurence for most people unless they are using dogs. 
I'm sure Oklahoma has a few lions, but not alot.  Seeing one would be an honor for sure considering a male lion takes up about 40 to 50 miles of personal terrritory and a female about 20 miles. 
In order to have alot of lions, they must have the right kind of habitat. Mountians, hills, canyons, swamps and a good deer population well support lions. 
Anyone can count themselves lucky to have seen one or more in a lifetime.........Good Hunting