Each church/denomination is different, so it's best to talk directly to the officiant (pastor, priest, rabbi, etc.) of a church you are considering. Many churches/clergy will marry non-members, although the costs will usually be more than for members. Most clergy also require talking to the engaged couple about their religion prior to performing the ceremony. Some people have used church facilities associated with a University campus, which typically perform weddings for people not affiliated with a specific church. They are often very beautiful locations, as often times are churches/chapels associated with the military or V.A. locations.