Divorcing him should be relatively easy. You certainly know where to serve him and he's not going anywhere. The real question is WHERE to divorce him. For any state to have jurisdiction to decide custody and parenting time matters related to your child, you will have to file in the state that your child has resided for the last six months. If you haven't lived in AZ for the last six months, the courts will need to determine which state has jurisdiction under the Uniform Child Custody and Jurisdiction Enforcement Act.
Please feel free to call me to discuss your case with me in greater detail.