I've been there twice, stayed in Ypsilanti which is about 10 miles east. Not ideal after a long game day and night out but we booked it at the last minute. I would reserve something now if you want to stay in Ann Arbor. We tailgated at Pioneer High School, kids walk around and collect your cans for the school too. While we ran in some nice fans, two guys in our group actually went without tickets and a random Michigan fan gave them free ones right in front of the gate but that was about it. People complain about WI and IA fans but Michigan fans are the worst in my opinion. I've seen us win and lose and like someone said, they were arrogant pricks the either way.
I don't remember too many specifics but I would recommend a visit to the Little Brown Jug as well. The drive can be tough coming home, assuming you're coming from MN and it will be around 10 hours, be sure to hit Chicago early on Sunday.