Advance preparation for emergencies is essential. Check out the American Red Cross's comprehensive site on preparing for emergencies: Being Prepared, American Red Cross.
The Department of Homeland Security also has some excellent checklists and forms, as well as a site for kids:
For guidelines on refreezing food when the power comes back on, visit the Food Safety and Inspection Service's page on Food Safety in an Emergency, as well as these additional sites:
Food Safety After a Power Outage, American Red Cross
Provides tips on safely storing your food and a chart to help you determine if your food is still safe.
Keeping Food Safe in an Emergency, United States Department of Agriculture
Fact sheet and FAQs on food and water safety including guidance on when to discard perishable foods.
Food Safety Office, CDC
Comprehensive food safety information.