If you're not sure what to do in Grand Rapids, head to Rosa Parks Circle. If there's a festival or event, that's the first place to be booked. In the GR Art Museum adjacent to it, there is a Grand Rapids visitors center in the gift shop. Just walk West on Monroe Center a little and you will see it on the South side with big glass windows.
It's where most of the big events happen.
GR Visitor Center in GR Art Museum next to Rosa Parks Circle.