Start with the main data page for the World Bank. Search for your topic (such as GDP or Foreing Direct Investment) or select Data Category to scroll through topics.
The United Nations Statistics Division (UNSD) compiles and disseminates global statistical information, develop standards and norms for statistical activities, and support countries’ efforts to strengthen their national statistical systems.
This site contains several UN data sources featuring global data.
The site also provides the Division's major publications covering demography, trade, national accounts, energy, industrial commodities, and more.
The ILO provides data on employment, unemployment, hours of waork, wages, migration and related topics.