CIA World Factbook
The CIA provides information on populations, military, government, and economic activity for nations recognized by the United States.
Harvard University Native American Statistics Project
This site is a research portal for individuals looking for statistical and demographic data about American Indians, Alaska Natives, and Native Hawaiians. All of the data on this site are publically (and digitally) available from their original sources – but this site brings them together in a user-friendly, intuitive manner. Although we realize that this is neither a comprehensive database, nor an exhaustive library, we hope that it provides a good starting point for research and facilitates access to a large portion of the current data about American Indians, Alaska Natives and Native Hawaiians.
Human Development Report
Provides ranks/comparisons of countries in addition to various statistics. It also allows you to build your own custom tables between countries.
World Development Indicators
This provides economic, social, demographic, and environmental information by region and country.
United Nations Statistics Division
Contains statistics on world development, social conditions, trade, populations, and demographics. Provides both international and domestic statistics.