Yes, from Michigan
I know that in Michigan, if you can determine the court where adoption was done, you can file to request information of a particular child.
You might also try some geniology divisions of the county clerks office where you believe might be near the area adoption occured at, normally close by to where the child was born. Geniologists research birth records all the time on a regular basis and have some darn clever methods. They normally belong to web rings, than cross file data by name.
Adoption records, I'm pretty sure are sealed in every state, but there are historical filings that normally precede and adoption which can be public, so searches at court houses, based upon name, might do some good. Unsure of that one.
I have a cousin that does Geniology, so I'll watch replies in case you get stuck, maybe she'll share some ideas.
Best of luck.