HELP!!!! I need Help!

My adopted parents wont give me my adoption records and are not helping me at all. I only know I was born in Akron Ohio on August 13, 1973 at 7:30am. in Akron city hospital, Summit county. Ronald B. Mitchell signed my birth certificate as the M.D. I remember my birth name as Angel, but that is all I remember of my name. I have a sister who was adopted with me. She was born May 24, 1975. Her birth name I think was Heather. Her birth certificate says she was born in Erie PA. We believe we might have a Younger brother. My name was changed to Anne Elizabeth Cooper. Her name was changed to Mary Margaret Cooper. We went through Foster homes before being adopted. We lived with our adopted parents in Erie PA. We now live in Ohio.If anyone can help please let me know. If you have any information that can be helpful to me it would be greatly appreciated. Thank you. I can be contacted at purplemoonleo@yahoo.com or purplemoonleo@fuse.net Thank you