Aha!Go 
Home exchange and vacation rentals. Initial use free, small charge after you actually make an exchange. Planning tools include a true distance finder.
http://www.ahago.com/Home Exchange International
Worldwide home exchange and apartment exchange for singles, single parents, couples and small families and vacation rental service.
http://www.singleshomeexchange.com/
Trippolis
Home exchange site for regions around the world. Forum, chat and FAQ.
http://www.trippolis.com
Prof2000
Home exchange for teachers. Includes penpals, host families and a travel pool. In English, German, French and Spanish.
http://www.prof2000.org
International Home Exchange Network
Global home exchange directory and membership service.
http://www.ihen.com/
HomeInvite.com
Global home exchange organization that offers properties for holiday home exchange or vacation rental.
http://www.homeinvite.com/
International Innkeepers Exchange
Exchange between Innkeepers around the world.
http://www.innkeepers-exchange.com
ExchangeZones
Offers home exchanges and vacation rental properties from all over the world.
http://www.exchangezones.com/
1st Home Exchange
International house swap service that lists offers for holiday home exchanging.
http://www.1sthomeexchange.com
Know Your Trade
A directory of home exchange clubs. Includes reviews of clubs, a forum, and home exchange tips.
http://www.knowyourtrade.com
JewettStreet.com
Worldwide accommodation network whereby people swap homes with each other.
http://www.jewettstreet.com/
Domity
Listings for home and apartment exchange and housesitting worldwide. In eight languages.
http://www.domity.com/
HomeWelcome
International and US home exchange listing browsable by location. Free listings; site is donation based. Also has directory of other home exchange web sites.
http://www.homewelcome.com/
