I've not been able to find regular John Deere checks either. But, there are places (for a majorly high fee, mind you) that will allow you to use your own pictures on the check.
John Deere people, you need to step up to the plate! You can get everything else with JD symbols on it - why not bank checks?! I don't want pictures of hogs/piglets and a tractor in the background - I want all JD products!