On Thursday and Friday parking is $2 per hour, and on Friday after 5pm as well as Saturday and Sunday parking is $5 per day at the convention center. However, parking is also free at some of the hotels downtown as long as you are a guest at that hotel.
There are also a myriad of metered spaces as well as parking ramps all over the down town area. And on some side streets there is free street parking.
We encourage you to car pool and arrive early at the Monona Terrace. There are several high profile events going on that weekend, and so parking may fill up at the Terrace. Not to worry though, there are a couple other parking ramps very close by.