A permanent resident card is also referred to as a green card.  Information and applications for applying, renewing and replacing are available at the Department of Homeland Security: U.S. Citizenship and Immigration site or by calling 800-375-5283.

The application for citizenship is the N-400 Application for Naturalization and details for fees and completing this form are also available on a section of the U.S. Citzenship and Immigration site.

Information regarding various types of visas needed for foreign citizens to travel to the U.S. are available on the Department of State: travel.state.gov site.