Popular Links:

CIA – The World Factbook:
https://www.cia.gov/library/publications/the-world-factbook/

Lonely Planet: http://www.lonelyplanet.com/

World Travel Guide: http://www.worldtravelguide.net/

Fodor’s: http://www.fodors.com/world/

Frommer’s: http://www.frommers.com/