How do I serve someone notice to appear in court without knowing their address?
I presume you are in the US. If you are filing an appeal, not a new action or countersuit, you don’t have to serve him personally. The papers he filed to get the restraining order against you should have some kind of address on it — if he used an attorney, it will be the attorney’s address, and you can serve the notice of appeal on the attorney. Otherwise, if you have to serve the guy personally, you know better than us. You will need someone to hang out on the streets where this person walks, or something. It shouldn’t be you, because of the restraining order.