Infrared camera

Get a home energy audit. If you're willing to pay for a more advanced energy audit, you'll probably see one of these gadgets. It's infrared camera that can locate hot and cold spots in a home--very important when you're trying to locate drafts and air leaks.

So rather than getting bids for solar panels, the first thing you should do it is arrange a home energy audit. Most are free services or you can pay for a more extensive offering where people will actually do some air-sealing or insulating on the spot. I recently paid about $600 for an audit and it was worth it for both the work they did and the advice.

A good resource for many home-related decisions is Sierra Club's recently launched Green Home Web site.