Attorney fees varies from attorney to attorney based on the attorney experience. Usually for this type of case there is no set fee. The filing and service fees are dictated by the code.
Darrell B. Reynolds,
Attorney and Counselor at Law
2385 Lawrenceville Highway, Ste D
Decatur, Ga. 30033
Without more information, this question is near impossible to fairly answer. You will have to file for custody in the County of the residence of the minor child. What I recommend is using AVVO to find a lawyer in the right county and schedule a consultation with that lawyer. Custody cases are determined by a Judge, so it is imperative that you hire a lawyer that is familiar with the Judges in the County where you are bringing your custody action.
You will have to file for custody in the county where the child lives. The cost depends on the attorney you retain, if it is contested custody matter, etc. Contested custody matters can be very expensive. I encourage you to contact a family law attorney in the county where your child lives.