I don't have any specific recommendations, but here is a group that can probably give you some very good information:
http://www.theprairieenthusiasts.org/who.htm
(clickable link below)

Another source of info is this site:
www.wildlifegardeners.org
It seems to have a lot of people knowledgeable about native plants in the Midwest (check the forums).

Here is a link that might be useful: The Prairie Enthusiasts