ISO Birthparents and Siblings-9/13/1978 Sharon PA

I am searching for my birth mother and father as well as my siblings(2 sets of twins). I was born September 13, 1978 at 7:52am in Sharon PA. I was adopted through the Children's Aid Society of Mercer County. All i know is that my mother was 21 and 5'2 and had the last name Johnson at the time. I was raised as an only child and would love to locate my siiblings as well as my birth parents.