DisasterAssistance.gov provides information on how to get help from the federal government before, during and after a disaster. It helps people understand the various forms of assistance available to them and how to apply for aid most efficiently, as well as find information about evacuating, finding shelter, getting food and water, getting medical services, locating loved ones, and recovering and rebuilding. Note that the registration period typically lasts 60 days, so it is important to register with FEMA quickly.
Via smartphone: http://m.fema.gov/
Via telephone: 1-800-621-3362