Iowa Great Lakes diving is OK in West Okoboji -- especially in late spring/early summer when visibility is best. Dives can be to 80-90 feet if you are so inclined. Bottom Structure, water intake towers, fish, a few tiny wrecks. Annual clean-up dive around Memorial Day.
Also some pit diving -- Big Blue in Mason City, Rutland Quarry, Ft. Dodge gyp pits. Not all are open to the public, tho.
Iowa Marine Biology -- Dr. Karen Stiles c/o Des Moines' School District travels to dive in FLA every spring break. Usually about 100 new certified students and about 40 tired parent/chaperone/divers.
There are a few shops: Des Moines, Ames, Ia Great Lakes.
Welcome back to dim water diving!