New York, NY 10010; (212) 807-8686, fax (212) 807-1001,
Amigos de las Américas: This group sends student volunteers to rural Latin American communities. Its projects emphasize community development and health care. 5618 Star Lane, Houston, TX 77057; (800) 231-7796 or (713) 782-5290, fax (713) 782-9267,
Experiment in International Living: This nonprofit group has educational trips, study-abroad and language training programs, and work exchanges for young adults. 63 Main St., Putney, VT 05346; (802) 387-4210, fax (802) 387-5783,
Hostelling International-USA: Even though this group is attracting more families and seniors, youthful travelers are still its focus. It has more than 110 hostels in the U.S. offering budget accommodations and other travel services. 733 15th St. N.W., Suite 840, Washington, DC 20005; (202) 783-6161, fax (202) 783-6171,
Let's Go: The popular student-researched guidebook series contains basic destination information for young, budget-minded travelers. Its Web site has government travel advisories, a forum for exchanging information and features. 67 Mount Auburn St., Cambridge, MA 02138; (617) 495-9659, fax (617) 496-7070,
Putney Student Travel: Programs offer high school students language and service trips. 345 Hickory Ridge Road, Putney, VT 05346; (802) 387-5000, fax (802) 387-4276,
STA Travel: STA issues international student and youth identity cards good for discounts worldwide. It also books student air fares, tours, packages and budget accommodations. Its Web site links to study and volunteer programs. Several offices are in L.A. and Santa Monica; (800) 781-4040, fax (480) 592-0876,
StudentUniverse: A good online travel service with economical air fares. You also can research international rail fares, book a hostel bed and get information on destinations and on studying and volunteering abroad. 100 Talcott Ave. East, Watertown, MA 02472; (800) 272-9676, fax (617) 321-3133,
Visions Service Adventures: Summer programs combine community service, outdoor activities and intercultural living in Alaska, Montana, South Carolina, Peru, Australia, the Dominican Republic, British Virgin Islands, Guadeloupe and Dominica. P.O. Box 220, 110 N. 2nd St., Newport, PA 17074; (717) 567-7313, fax (717) 567-7853,
Connecting Solo Travel Network: This not-for-profit, member-driven organization was founded by experienced solo traveler Diane Redfern. It publishes a newsletter six times a year and maintains a Web site with tips, news and information on companies friendly to single travelers. Membership is $25 on the Internet, $35 by mail. 689 Park Road, Unit 6, Gibsons, BC V0N 1V7, Canada; (800) 557-1757 or (604) 886-9099, fax (626) 608-2139,
O Solo Mio: The company offers tours for singles and can match you up with a roommate. 160 Main St., Los Altos, CA 94022; (800) 959-8568, fax (650) 941-5334,
Travel Alone and Love It: Flight attendant Sharon B. Wingler is author of "Travel Alone & Love It" (Chicago Spectrum Press, $14.95). A Q&A, tips and resources are on her Web site:
Travel Companion Exchange: A long-established service that helps solo travelers find companions (one way to avoid the single supplement) and publishes a newsletter ($48 for a year, $6 for a sample) with tips and bargains. P.O. Box 833, Amityville, NY 11701; (631) 454-0880, fax (631) 454-0170,
FAMILIES, SINGLE PARENTS
Baby Center, Parent Center: Baby Center seems like an online shopping site, but look further (under "Topics A-Z") and you'll see travel advice for expectant parents and those with toddlers. The affiliated Parent Center has destination stories, tips, bulletin boards and useful travel information for parents of older kids.
Fodors: On the guidebook series' Web site you'll find tips for traveling with kids, information on buying car seats and kid-oriented city guides.