House and property owners are in the public record, so it is easy and perfectly legal to find out who lives next door. Be sure to obtain current information, as house and street numbers can change over the decades, and a neighbor's house might have a different zip code.
Once you have all the correct information, call the your local city or town hall and request to speak to someone in the tax assessor or tax receiver’s office. They should provide the information over the phone, but office policy may dictate that you come in and do your own research. You can also find out the home or property owner next door by looking at the deed, which shows both the buyer and the seller.
County property tax assessor websites have property owner information. Typing in phrases such as “recorded documents," “assessor’s department” or “finance” into the websites search bar may ease the search. If unable to find what you're looking for, try a property search website not connected to the county or city. Some websites are free. Others charge a small fee. For a small fee, you can also hire a professional from a title search company to find out who owns the house.