CIA World Factbook
This web-site contains a lot of good information about different countries including maps and statistics.
Employment Conditions Abroad Ltd
This UK company manage a 'cost of living' index for many countries and will, for a fee, supply you with details about any of the countries in its information.
NationMaster.com is a massive central data source and a handy way to graphically compare nations. NationMaster is a vast compilation of data from such sources as the CIA World Factbook, United Nations, World Health Organization, World Bank, World Resources Institute, UNESCO, UNICEF and OECD. Using the onsite form, you can generate maps and graphs on all kinds of statistics with ease.
Population Reference Bureau
An interesting site with all the information and statistics you need about world, continent and individual country 'population'.
Statista is an international statistics platform on the web. With data on over 60,000 topics from over 18,000 sources, we offer an extremely broad spectrum of information.
UK Department for International Development
An informative web-site which includes 'Statistics on International Development'.
US Census Bureau
This web page allows you to obtain summary demographic data for one or more countries.
Wholesome Words 'Worldwide Missions'
This U.S. page entitled 'Great Commission and the Harvest Fields' has collated a number of interesting physical and religious statistics about the world.