Ike's Guide

Reducing Energy Costs has very practical information on how to retrofit a house to make it more energy efficient. For example: if you have single pane windows and can't afford to upgrade to double panes, this book has advice on how to add a layer of plastic to simulate a second pane. It also has information on how to improve insulation and clean appliances so they run properly.

The Solar Living Source Book has great information if you are interested in living off the grid. It includes detailed information about infrastructure for generating your own energy, and also suggestions for efficient appliances. This book gives good background and also specific brand names and prices so you can really get a feel for what different approaches take. Some of the material is probably only useful if you live in a rural area, but still a great read.

The China Study isn't directly about reducing fossil fuel usage, so consider this one a bonus. It is an interesting analysis that claims that a diet with about half the normal amount of meat will dramatically reduce our chances of contracting cancer, diabetes, and heart disease. There is also a tenuous connection between meat and energy consumption, the general rule of thumb is 10 times as much energy is needed for meat as is needed for plant based foods. Anyways, thought this book was really interesting, definitely worth a recommendation.