If you live in a typical U.S. home, your appliances and home electronics are responsible for about 20 percent of your energy bills.  Here are some tips to reduce their energy consumption:

Shopping for energy-efficient appliances
http://www.eere.energy.gov/consumer/your_home/appliances/index.cfm/mytopic=10030

Power-control devices for home appliances
http://www.eere.energy.gov/consumer/your_home/appliances/index.cfm/mytopic=10060