You certainly couldn't have guessed at the first step -- it's to open what's called a "paternity file" with the court, since you weren't married. This file serves as a sort of umbrella for handling decisions on custody, visitation, child support, and restraining orders for unmarried parents.

More and more courts have a person on their staff who will help you wade through the necessary forms and get a court date set so that you can get a custody order. Call the court's clerk to see if they have such a person. Even better, see if you can get legal help and other support through your local battered women's shelter.

Once you have a custody order, it will become an important piece of paper. Mention it to a police officer, and he or she will become infinitely more willing to offer protection if your ex tries to see the baby when he shouldn't.