What should be plan to see and do on our trip to S. Dakota?  

We are hoping to travel to S. Dakota in September. Have you been there, maybe live there? What besides the Badlands and Mt. Rushmore should we try to see? It is a totally unfamiliar place for me and I'll probably not ever get there twice, so what should I be sure not to miss?

I saw a post that said the economy is poor there. Does that mean that the cost for traveling there will be lower? Maybe we can stay longer if it doesn't cost so much.

What are the Indian Casinos like? Are they expensive? I don't gamble, so wouldn't be interested in gambling, but they have restaurants in them, right? Are they also hotels?

Do you know what kind of clothing we will need for the weather there in September?

Where are the airports? Rapid City? Where else? We might find it cost effective to fly there and rent a car for seeing the state. I don't even know what cities have airports!

Sounds like I need to do some research. Anyone got any advice?