In the last few days, I've tried a number of cheese from Neil's Yard Dairy (after a recommendation from a friend). The "farm cheeses from the British Isles" are fantastic! A stilton, wensleydale, shropshire - excellent. If you like cheese I highly recommend picking some up. I have yet to try their cheddar, but I've also heard good things.
In the Bay area, I've found some at Whole Foods and the Cow Girl Creamery in the Ferry building.