Petition for (Custody) (Visitation). Where to File for Custody.Custody cases are usually started in Family Court. File for Child Custody. Notice of the Petition must be given to the "parents" of the Minor. Type of custody action. You can file a petition for child custody in your county's Superior Court. If you are divorcing, the petition will be included in your divorce papers. A petition for custody would be filed in the juvenile, family, or domestic relations Court with jurisdiction over the child, at the county level. Each of the documents listed below inculde a blank form and the instructions to fill out that form.