Here is the site for List of the States of the World.
Until it is ready, you can use:
* List of UN member states and UN non-member states - permanent observers
* List of States with limited recognition at wiki.gov.world
* IANA (ICANN) root zone database
* UNGEGN List of Country Names (2012)
* Russia's MFA list of States of the World
* countries.world - lots of rankings and indicators