How do I go about changing my sons last name to his fathers in the state of TN ?

Get the consent of his legal father, file the necessary paperwork and pay the applicable fees.

The court clerk will be able to direct you to what you need to file.

OK thank you. I called clerk and they can't tell me anything because they are not lawyers. They can't tell me where or how to get the paperwork. It's frusturating! So I'm going to contact a lawyer.

OK thank you. I called clerk and they can't tell me anything because they are not lawyers. They can't tell me where or how to get the paperwork. It's frusturating! So I'm going to contact a lawyer.

OK thank you. I called clerk and they can't tell me anything because they are not lawyers. They can't tell me where or how to get the paperwork. It's frusturating! So I'm going to contact a lawyer.

OK thank you. I called clerk and they can't tell me anything because they are not lawyers. They can't tell me where or how to get the paperwork. It's frusturating! So I'm going to contact a lawyer.

ok thank you. i called clerk and they can't tell me anything b/c they are not lawyers. They can't tell me where or how to get the paperwork. It's frusturating!! So im going to contact a lawyer.

No - they "wont" tell you anything. I can almost promise you that they know.

A lawyer, or probably a paralegal might be the best way to go. It shouldn't be terribly expensive, but it sounds like you local court is not as user friendly as many.