What needs to be accomplished here is a termination of parental rights (TPR) and a subsequent adoption. While I would encourage your son to use a local family law attorney, it is possible to handle the matter without an attorney.
If your son desires to proceed without an attorney, he could go to the local courthouse for the paperwork. He would need to request a packet for both the TPR and the adoption, the packets will contain the template documents necessary to facilitate the process. Your son would need to fill out the documents and then file them with the clerk to get everything started.
This would be the cheapest way to handle the matter as it would only involve the amount of the associated court fees.
Please let me know if anything requires clarification.
I hope you found my answer helpful. If so, please click on the green ACCEPT for my answer. This is necessary for me to be paid for my work and so that I can get credit for assisting you. Even if you are a subscription member, you will need to click ACCEPT. Your question will not close, and you will still have the opportunity to follow-up if needed. Leaving a bonus and positive feedback is not required, but doing so is certainly appreciated! Thank you and good luck!
Also, several customers have asked how they may direct a question to me in particular. If you specifically want me to assist you in your legal matter, just put "FOR JOSEPH" in the subject line and I will gladly pick up the question as soon as I am on-line.