Looking for my birth father and other sibilings that maybe still in Arizona

My name is Nikki-Yolanda Thomas, I was born in Phoenix, Arizona to a Sandra Edwards on February 26, 1979. I recently a year ago have located and spoke to my biological mother and sisters and brother. She does not remember my father, in my records it states that my father's name was Authur (I do not have a last name). I think that he would be 79. I think? I would like to find my father and other sibilings. I am also, looking for my biological sister that was given up before me as well. I think that she was born in 1976, because my older sister's Paula is 34 and our sister Nickole is 33, she would be born before me ( I think) from what I was told. Please if you have any other information, I would really appreciate it. Thanks! Nikki-Yolanda Thomas