True to my name as the Secret Agent Librarian, here is a cool site for secret agents. It really is published by the CIA. Fortunately, you don't have to be a secret agent to use the CIA publications page. They have two cool reference tools: The World Fact Book and World Leaders.
The World Factbook give updated vital statistics information on every nation in the world, i.e. type of government, population, GDP, etc.
The World Leaders allows you to find out the chief of state and its cabinet ministers.
So next time you go on a secret mission you will know all about Burkina Faso, Tokelau (a territory of New Zealand) or Svalbard (a territory of Norway).