The United States Department of State is responsible for issuing passports. You need a passport any time you leave the country because even if another country does not require it to get in, the U.S. will require it for re-entry.
Expedited passports generally take between two and three weeks, according to the U.S. Department of State website.
Anyone can request an expedited passport but must pay an additional $60 fee (as of February 2010) in addition to the other applicable passport fees.
The U.S. Department of State's stated goal is to have the application processed within five business days from the time it arrives at the agency or the day the expedition request is approved.
U.S. Department of State encourages applicants to write "expedite" on the outside of the envelope to make sure the application gets sorted appropriately.
Applicants can check the status of their passport online at the Department of State's website (see resources). Applicants need name, birthday and the last four digits of Social Security number to check the application.