Most of what you are looking for will be in either the Green Acres or Midwest Messenger -- Events section. A call to the listed pull contacts will give you a good indication of what "stock" classes they will have if not listed. That being said, don't be surprised if you pull against some stock machines that have multiples the horsepower you have.
If you have a true farm stock tractor, pulling in southeast Nebraska won't be fun for ya!!! I pull a stock tractor and I only go to three pulls a year In Leigh, wahoo, and Arlington Nebraska, I pull the 14,500 and 16,500 class with a 4440, these three pulls are pretty much stock for my two weight classes, I've been to Springfield and they have no rules and maybe one for two true stock tractor down there
