I have a question about the ceilings the various states impose on deferred compensation. Is there a resource available to look up all the states' limits in one place?

Not really. I have a list of state retirement systems at http://benefitsattorney.com/states.html. But in some instances, particular employers within a state maintain separate deferred compensation plans. And in others, state law other than that governing the statewide retirement system(s) will impose limits on the deferral of compensation.