Hi James,
I think you will find that people don't trust you now that they know that your brother-in-law is Jon (not really, we love Jon
)
Do a search of the local car clubs. Enter Oklahoma City and Sports Car Clubs and see what you get. Then go to the individual web sites and see if they have a competition or autocross director. Once you do that you contact them and they will have their fingers on the pulse of what is going on autocross/soloII wise in your area. Don't forget to check the SCCA. Also, often sports car clubs will operate on base. Some of the best events I have ever been to were on military property.
This time of year, the club boards are in the planning stages so they might not have a calendar filled up just yet.
Do you have a 914?