trying to find sister.

Hello, I want to ask A serious question, I'm looking for my possible older sister, I don't want to give too much information so ill just give you the essentials, back when I was just 16 my father called me after 3 years and told me that I have a possible older half sister i'm am now 18 and soon to be 19. I don't know her name or exactly old she is but I do know that she is white and have red hair and my guest is that she is 20 now. apparently her mother gave her up for adoption, when they asked her who the father was she gave three possible leads my father, and his brother. they came to my father while he was in prison and showed him the baby's pictures he and my uncle denied and said they were not the father. they labeled them as, "possible". they also gave a copy of the baby's files and a picture of her to my mom. when I ask my father for anymore leads he tells me to stop worrying about it and when I ask my mother for the files she tells me to not obsess about it. I understand she doesn't want me to let it consume me and wants what's best for me best for me but I feel like its important for me to meet her because family is important to me, plus I've been getting my priority straight I just recently graduated high school, and after summer break I'm gonna start going to collage to improve my art and writing and my mom is going to help me get a job at the casino by our house. but I am planning on going to child protective service and show them the information I know and see if they can give information's on were she is living. but I need more info any advice for looking?