Hi Chris,
First of all, It's morning for me as well, because I live in the Netherlands

. And I also visit Flying Legends often, almost each year. In my opinion it's one of the best shows I've ever seen in my life.
Secondly, the USAF museum is located near the city of Dayton, which is about a 5hr drive from Chicago. I think it is the best option is to fly to Dayton, because there is no direct public transportation to the museum and I suppose a taxi drive will be too expensive.
Thirdly, the only option to reach Willow Run by air is to fly by yourself, there are no (commercial) airlines who fly to the airport. This is because it normally is GA airport. And I think it's a good idea to reserve a hotel by Christmas because many of them are early booked for for example many flying crews.
And lastly, in 2010 there was indeed a huge gathering of B-17's, almost each Flying Fortress (7 pieces) from the USA were present at the airshow. In 2011, only one B-17 will be at TOM. But that totally depends on the annual theme. Such as this year, it will be a memorial airshow for the USN because of their 100 years birthday. So not many (old) USAF will attend. But in 2012, that can be totally different.
I hope I've answered all of your questions. If you would like to ask more, feel free to ask.
Roderick