Hey Glen:
Only "Dumb Question" is the one you don't ask. I'm sure crappie can be caught year around in OK and everywhere else. We do well on them here in Arkansas through the winter and we're right next door.
You just have to figure out where the little critters go or better yet fix them a place to hang out for the winter. They gotta be somewhere and they gotta eat somtime!
Hopefully some folks that fish in your area will respond to this post and get you headed in the right direction.