From the Sept 2011 Topeka Control Line Association newsletter...
I don't know any additional details about what is going on in Topeka, but that's what was in the newsletter. It might be wise to call someone in the club to coordinate something before making the trip.
Good advice and if you find out any additional information please post it here for others to see!!!
It is not just America!! In addition to the US and Canada, Australia, Brazil, Italy, South Africa and the UK are all going to fly Ringmasters for the event. New Zealand seems to be in the missing category so far.