Go to the Genessee County Court building on Saginaw St., in Flint. When getting there, the room is the first door to the right, when coming in the West door.
There is several ways to go.
1. Requesting non-identifying information, it cost about 30 dollars. This will give you all information like, where his parents were born, medical (if its listed), where they may have worked. I was able to track a mother down using this route.
2. Request that the records be opened. This will cost you more money. They will assigned a mediator to research to see if birth parents are alive or not. He/she will gather all the information then you will talk to a judge. I just got a record opened for someone this way and working on another.
3. There is also a form you can put in the records to allow his birth parents to search. In the same token, they may have done this to allow him to search.
So you need to go to the court house. Hope this helps you.