You can visit www.lennox.com for excellent information on services. They provide the best when dealing with heating and cooling systems. All systems are energy efficient and can save you money in the long run.
Wikipedia have information on electric heating systems including the types of heating systems that are available. One can also find information on 'Which' including the costs and advantages of these heating systems.
You can find ratings online in many places for heating and cooling systems. You can go to the website of the store you plan on purchasing them through and they will have a list of customer reviews and you can compare the different systems side by side.
The best information on geothermal heating and cooling will come from your local heating and cooling professional, who will evaluate your situation and help determine what product is right for you. There are many websites that offer general information on geothermal heating and cooling as well, including Earth Comfort, Geo Comfort and Energy Star.
One can find information on heating and cooling repair companies by looking in the local phone book. Most of the time there will be advertisements in the phone book and in the mail that offer these services.
There are many sources of information on geothermal heating and cooling, but I would start here: http://en.wikipedia.org/wiki/Geothermal_heating You can also find videos about it on youtube.
It all depends on what type of heating and cooling system you are looking for. You can go to www.bryant.com to get a general idea for getting heating and cooling systems, but a local company may be cheaper. You should also consider maybe an air conditioner and a space heater for the super cheap way.
Their are several websites that can help you find more information on Geothermal Heating and Cooling such as Wikipedia, energysavers.com and geoexchange.org.
Without knowing where you are located, I can answer generally but not specifically. Home Depot (located almost everywhere) specializes in heating and cooling systems starting as low as $299.
If you are looking for information on buying a new heating and cooling system for your home I would visit: www.searshomeservices.com/central-heating-air/improve
type in google/bing heating and cooling facts.
You can find out about HVAC systems through local air-conditioning/heating companies, or you can also find information online at sites such as www.lennox.com to find all of the info.
"Universal Heating & Cooling" has an office in Atlanta, they can do commercial cooling systems. You can discuss your businesses' cooling needs with them at (678) 392-2839.