A list of immigration numbers can be located on numerous websites. All United States Citizenship and Immigration Services phone numbers can be located on their official website. It is recommended when searching for a governmental phone number, such as immigration numbers, to use an official website. However, there are numerous websites that offer a complied list of immigration phone numbers from different countries and jurisdictions. Often times, it may be beneficial to contact a nearby embassy or immigration services office to ask for a hard copy list of phone numbers and other elements of contact information.