I am a single mother of a 6 year old boy. My son has never seen or spoken to his dad. I am in the process of finding my son's father. But I need to know how to go about getting his rights taken away if if he chooses not to be in my son's life.

Get married and have your new husband adopt your son.

That's basically the only way you will get his rights terminated. But, if the father chooses not to be a part of his life, why bother getting rights that are not being used, terminated.