I'd say you could also research and talk with architects who are specializing in this area, and who are LEED certified. Hope this helps.
Here is a link to the builders site as well:
I wrote an article on "green houses" recently and here is the link for your review: http://www.rehubbub.com/blog/author/vero-mendelson/
You may find some interesting suggestions on how to turn a regular home into a greener home. Also, check with banks as some of them are proposing "green mortgages".
There aren't many green homes because, basically, it's more expensive to build a green home than a standard home. As people become more aware of environmental issues, I think the demand will increase, which will cause an increase in supply. In the meantime, there's a lot more buyers willing to spend an extra $5K on granite countertops than spend that same $5K on a rainwater collection system or energy efficient lighting.
I've written some Industry Information articles about some different Green Building options and what the cost for each of these is in my market - that might get you started on some idea of the costs involved in green building.
It can also be expensive to even have a new home certified as a green built home, which involves some extra, third party inspections and qualifications.
I had gotten involved with an Energy Star certified builder a few years ago and he built an Energy Star certified home which is a more energy efficient home. It just so happened that fuel prices Peaked at that time to 3.00 a gallon. It was a huge issue. I thought that the timing was perfect and I did a lot of marketing to promote the efficiency of the home. I was shocked that I did not get any calls about it. When buyers did call about the house and I mentioned it was Energy Star rated. Not one seemed to care. Total ambivalence. I was shocked.
I am now running into more people who are asking about Green Homes. I think this is because our energy problems are at front and center stage nationally and people feel it is only going to get worse.
The problem is that people are very enthusiastic about building "Green" until they learn that it costs more to build these homes, So ultimately I think you do not see it because most people are not willing to pay any amount of premium for a better more efficient home. But again, I am seeing more interest in this and this will eventually translate into more people building Green.
The other issue I have run into is everyones definition of a Green home is different. Some want all natural non toxic renewable materials to be used. Others think it is energy efficiency and geothermal. Which is fine. But I find I have to ask buyers what they mean by green construction. Some simply use that term to mean that they do not want any carpeting in the home!