Scott: I wonder if the California regulations you refer to are at all similiar to the International Energy Efficiency Code. That is, the building as a whole must comply with a certain value, which can be achieved even with cheap windows if the insulation (or other factors) are done well. There is free software available that you might find interesting to determine compliance. One is called "MECcheck" and could be easily found with a search. Also try searching "ASHRAE" for another software. Sorry I don't have the URL's on hand.
When you go to Depot or Lowe's, I'm sure you'll see the fans I speak of. Take care.
