Just posting about this in case there's anyone here in the Midwestern US who is interested:
The U.S. National Amateur Sumo Championships are going to be taking place this Saturday, June 13, at the Parkville Athletic Complex in Parkville Missouri.
Address: 6014 MO-9, Parkville, MO 64152
The winners at this tournament will get spots to represent the US at the World Sumo Championships this August in Osaka.
There's not a lot of info online about it right now, but this will be the place to see it when more emerges: http://www.americansumo.org/
Yours truly is planning to compete as a birthday present to myself, as I turn 27 the next day. I've been lucky to get some guidance and training from a few people with professional and amateur experience in Japan, so I'm hoping to see what the competition is like at the national level!