Power Adapters & Converters
"How to Choose Power Adapters & Electrical Converters for UK Travel Article" on About.com (click on orange link). Bottom line: check your devices to see if they are dual voltage (110-240v): if they all are, you do not need to buy a pricey converter.
US to UK adapters can be purchased at Radio Shack, and probably Walmart as well. If you are an Amazon shopper, here is a link to a list of adapters.
Link to appropriate power converter on Amazon: click here