Greyhound (800-231-2222, www.greyhound.com) offers passenger bus service countrywide, with terminals in Washington (1005 First St. NE), Arlington (3860 S. Four Mile Run Dr.) and Silver Spring (8100 Fenton St.). Bus service from Washington to New York City is $22.50 one way with seven-day advance purchase (based on round-trip purchase); walk-up fare is $35 one way. Peter Pan Bus Lines (800-343-9999, www.peterpanbus.com) serves the Northeast Corridor and shares terminals with Greyhound in Washington and Silver Spring (but not Arlington).
Several other companies offer service to New York City. Today Travel(www.ivymedia.com/washingtondc) offers a bus to Manhattan's Chinatown for $20 one way, $35 round trip, with pickup at 610 I St. NW. Washington Deluxe (866-287-6932, www.washny.com) has service to several locations in New York City for the same price, with pickup at K and 15th streets NW or New Jersey Avenue and E Street NW.
Organizations offering tours include:
Smithsonian Associates (202-357- 3030, www.residentassociates.org) offers local study tours via bus to nearby areas, including Antietam and Ellis Island.
Gold Line/Gray Line (800-862-1400, www.graylinedc.com) offers trips to Atlantic City (Thursday through Saturday, $32 round trip, with $17 in coins given back for redemption at the Tropicana and Sands casinos), Williamsburg and other spots.
Trafalgar Tours (866-247-9880, www.ttusa.trafalgartours.com) offers luxury motorcoach tours throughout the United States, including Hawaii, as well as Canada, Mexico and other international destinations.
For other carriers, check the Yellow Pages under "Sightseeing Tours" and "Buses -- Charter & Rental."