Good General Information for an International Student:

• H1B Visa Jobs: job info., and advice
• International Students: job info., Visa info., and much more
• My Visa Jobs: great tools and reasources
• US Chamber of Commerce Abroad: See "AmCham Direcrtory"  

These are good job/internship sites:

• Adzuna: Jobs in the UK 
• BUNAC - Work and volunteer programs abroad
• Career Builder International - great links
• Career Jet UK: search multiple sites in the UK
• Escape Artist - jobs overseas, search by category and location
• Federal Goverment Jobs - US State Department
• 4 International Careers and Jobs - search by country and category
• Go Abroad - Jobs, volunteer, study, intern, teach abroad
• IHipo: international jobs and internships
• International Jobs - Comprehensive, but charges a fee
• Jobs in the sun - Cayman Islands and Carribbean
• MONETOS is a comprehensive international research and information portal, about living in the European Union. Not a job site, but loaded with great information. 
• Monster UK - jobs in the UK, but there are links at the bottom of the page to other countries
• Overseas Jobs - Just what the title says
• Students Go Abroad: internships and volunteer opportunities.
• The Network - jobs in 70 countries
• Volunteer Abroad - No jobs, but many great opportunities to serve