Step father wants to serve process on the ukrainian father for adoption in USA - How?

I am the step father of a ukrainian child now in the USA. How do I serve process on the ukrainian father to notify him that I am starting adoption proceedings to adopt my step-daughter in the USA? I want to use a local process server as the international process server wants $600 +. I know there is a process to follow per the website. Does anyone know how to find a local process server to serve process on a ukrainian person?