Statistical Yearbook : The Statistical Yearbook provides in a single volume a comprehensive compilation of internationally available statistics on social and economic conditions and activities, at world, regional and national levels, for an appropriate historical period. It is prepared by the Statistics Division, Department of Economic and Social Affairs, of the United Nations Secretariat.
CIA World Factbook: Select a country and the facts you would like to know about the country.
The Organization for Economic Co-operation and Development (OECD): Dedicated to promote policies to help social and economic well-being for people world-wide.
U.N. Human Development Reports: Provides statistics regarding gender development and inequality, poverty index and more for countries all over the world.
World Bank: Go to topics tab and examine poverty, poverty analysis, measuring poverty, or measuring inequality.
World Trade Organization: Information for key "infrastructure services (like transportation, telecommunication, finance and insurance) for over 90 economies.
Use Google Scholar to find articles from a wide variety of academic publishers, professional societies, preprint repositories and universities, as well as scholarly articles available across the Web. A drawback is that not all articles are free.