I agree that Build it Green is probably your best bet for information. In San Francisco, there is a company called Lorax Development (www.loraxdevelopment.com) who build green from the ground-up.
Also, you should check out What's Working's website (www.whatsworking.com).
Things to consider when building green are the local laws around grey water use and rainwater harvesting, and bioclimatic architecture (how the site and home can work in harmony to optimize the living comfort, light, and air flow).
Another great company doing sustainable and very beautiful homes is Living Homes (www.livinghomes.net) - Mon Jul 23 2007, 14:59
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