I only know that my birth parents were teens living in the small city I was born. Where can I try to find them?

Why do you need to find them? :)

First have you talked to your parents ( the people who raised you, adopted you, assuming you were adopted)

Often they know more than they tell, when my mom died last month, in a small book, was all about my adoption, names of my birth parents and more. For me when she died.

But if you know their names, in a small town, you call everyone with that last name and ask questions.

How old are you? When were you adopted?