American Citizens Abroad is a non-profit organization which aims to represent Americans living abroad. The organization has a network of individuals spanning more than 60 countries.
www.americansabroad.org provides a wide range of information on topics such as taxes, banking, voting, citizenship, social security, FATCA (Foreign Account Tax Compliance Act), the FBAR (Foreign Bank Account Report), Medicare, and healthcare.
Citizenship Requirement FAQs and Table of Transmission Requirements are also available, both of which can assist in determining whether an individual is a U.S. Citizen.
Action Item: Check out this useful resource for Americans in Canada or abroad.