Wondering

There are so many questions associated with green home building!  Its overwhelming because there are many different opinions on what is best, but one criteria I MUST meet is affordability.  Green can be very expensive!  Take solar panels for example, we live in a great region for solar energy, but because of the price tag there are very few solar powered homes. 
This list covers the areas I plan on researching, but who knows what new questions I will have during the process.

• exterior walls
• insulation
• heat
• air conditioning
• solar panels

Exterior walls:  Should I use a stone exterior wall because of its ability to hold in heat and cool?  Is it affordable?  I definitely love the look of stone exterior, and it is low maintenance which is great.  I spoke with a contractor who suggested using real stone veneer.  This product is real stone but its only about an inch thick instead of being a regular rock.  This sounds interesting and may even be something my husband and I could do ourselves to save money on labor.  One question I forgot to ask the contractor, What type of trim would I use on the exterior and how would I connect it to the stone?  I have a feeling my contractor friend may get tired of me during my inquiry. : )
Insulation: There are lots of different choices for insulation.  I definitely want insulation in the exterior and interior walls.  What kind of insulation should I use?  I want it to be a green natural product so it won't emit any harmful gas.
Heat and A/C: I watched an interesting show on geothermal heating and cooling.  This type installation is not very common around here yet, but I did find some online in Atlanta.  The tv show made it sound very expensive, but that has been a couple of years ago so maybe there is more information and lower prices.
Solar Panels: To live on the grid or off the grid.  Hummm, I think it would be really cool to be self sufficient and get a check from the power company each month, but is the initial price and the price of upkeep less than the savings.  I really want to find out how solar panels work and what the day to day upkeep involves.  There is a solar power company in Mansfield, Ga  that I am planning on visiting, I'm sure they can answer all my questions.

I have a lot of questions so far and very few answers!