Buy the most efficient dishwasher, washing machine (front loading), and refrigerator you can afford. These are major energy users in your home.
Get the $8.95 ACEEE (American Council for an Energy-Efficient Economy) Consumer Guide to Home Energy Savings ACEEE has done your homework for you! They have sorted through the thousands of major home appliances and heating and cooling systems on the market and picked out those that are the most efficient. The guide covers:
Buy Energy Star rated computers, printers, monitors. and appliances. 
Don't run your mostly empty refrigerator in the garage! This old beast can cost you $10 to $20 a month. Don't you have something better to spend your money on?
Recognizing that the world's dependence upon fossil fuels has invariably led to the devastation of our atmosphere and environment, we have strived to demonstrate the need and practicality for renewable energy technologies that are clean, cost-effective.
American Council for an Energy-Efficient Economy
The American Council for an Energy-Efficient Economy is a nonprofit organization dedicated to advancing energy efficiency as a means of promoting both economic prosperity and environmental protection.
The Washington State University Cooperative Extension Energy Program (WSU-EP) operates the Energy Ideas Clearinghouse. Information on 5,000 products and technologies.
DOE - FEMP Energy Efficient Products
Product energy efficient reccomendations, the Federal procurement challenge, and sharing energy savings success.
ENERGY STAR Qualified Products
Products in more than 40 categories are eligible for the ENERGY STAR. They use less energy, save money, and help protect the environment.
Green Lights is an innovative, voluntary pollution prevention program sponsored by EPA, the primary purpose of which is to encourage U.S. organizations to install energy-efficient lighting. The site provides benefits of the program, and links to downloadable software tools.