Are you looking for classes in the local shoots, IBO, ASA or NFAA? I make a list of over 500 shoot dates from MN, IA, NE, SD with some in MO, WI and IL.
I usually recommend calling the local club to find out who's rules they use, or if they have their own. The IBO, ASA and NFAA have their own websites you can check out for class rules. You could also just ask them when you get there, they'll tell you what class your equipment is in, and what stakes to shoot from. If you need anything further, just ask.
South Dakota - Iowa