Linds and I have been talking about last names, and trying to decide if we want to make any changes to our last names once we're married.
On a whim, I just googled "name change michigan" and found out that if either of us want to change our names, we need to pay $150 to file a petition to Washtenaw County's probate court. We then need to go get fingerprinted, await police clearance, and then schedule a hearing in which we explain our reason for the name change. The process apparently takes at least two months--and then, assuming our petition is accepted, we have the usual month-long stream of paperwork for things like driver's licenses, social security cards, etc.
For Linds and I to both change our names in Washtenaw County, we'll have to pay $300. A marriage license in Washtenaw County costs $20--name change included.