This DOE site provides a compendium of useful information about geothermal technologies.
The Geothermal Energy Association provides a number of publications along with their All About Geothermal” guide to geothermal technologies.
Comprehensive site with contractor lists, technical and financing information.
This site is a good resource for anyone interested in owning a Geothermal Heat Pump System. This site introduces the technology, addresses many questions and provides a list of consultants.
This site introduces Heat Pump technology, its energy benefits and also provides purchasing tips. The site was created by Flex Your Power, an energy efficient campaign sponsored by the state of California.
This is a more in depth tutorial to heat pumps and concentrates on Geothermal pumps. This site introduces the technology, provides diagrams and discusses the efficiency benefits of a Geothermalsystem.
This site is a good resource for consumers interested in purchasing a Geothermal Heat Pump. The site covers Heat Pump rating systems, economics, and site evaluation. It also briefly discusses instillation.