While there are more people in the northeast, or in Florida, I believe there is a much higher percentage of gamers in the Midwest. Here in Madison, a city of less than 250,000 people, there are six gaming stores. Six. And an incredibly active RPG community.
Wisconsin is the epicenter of the RPG universe and I think it would be appropriate for the D&D museum to be where it all started. Lake Geneva is quite a tourist town already and the D&D museum would add to that. Real estate there is reasonable, I expect the town would embrace it, and you would have no problem finding special guests and having lots of enthusiastic volunteers.
Wisconsin is the epicenter of the RPG universe and I think it would be appropriate for the D&D museum to be where it all started. Lake Geneva is quite a tourist town already and the D&D museum would add to that. Real estate there is reasonable, I expect the town would embrace it, and you would have no problem finding special guests and having lots of enthusiastic volunteers.