Looking for birth family

I am a male born on June 1, 1978. My birth certificate says I was born in Crawfordsville Indiana. I think I was adopted through a Huntington Indiana agency or the court system, not too sure. Not knowing much has held me back on finding where and whom I come from. The small things I know is that my mom and dad where not married and had kids of there own but do not know if that is true or not. That is about it. If anyone could help I would really appreciate it. Thanks Ryan