I recently bought a new home and I recalled an amazing site.  You get out of this what you put into it, but ultimately you will get, in order of return on investment, the best upgrades /repairs for your money to save energy.   I can’t understate how helpful this is for identifying and allowing you to decide how to save both money and energy usage in your home.   They have a quick set of questions, or you can dive into the full section, but expect to invest an hour of time or more depending on the complexity of your home.   See for yourself!

http://homeenergysaver.lbl.gov/consumer/quick-general