Installing a booster Pump is not that difficult, infact Davey Pumps makes a pressure boosting system specifically for houses with low water pressure.
Basically it is a pump with a pressure switch that turns on the pump, and a flow sensor that turns off the pump. The advantage of the flow sensor is that the pump will remain running until the taps are shut off. Davey has been selling this system in Australia for the past 8 years and now has started selling them here in the US. For more information you can visit their web site at http://www.daveyusa.com or call 866-DAV-PUMP