3 links
iJET Travel Intelligence
ijet.com
Commercial organisation providing detailed travel advice and warnings for various destinations.
U.S. Department of State: Travel Warnings & Consular Information Sheets
travel.state.gov
US government's official travel advice and travel warnings. Registration for automated email updates.
UK Foreign & Commonwealth Office: Travel Advice by Country
fco.gov.uk
British government official travel advice and warnings for all countries.