Peanut butter sold in the UK is very different from the typical kind available in grocery stores in the U.S. The kind readily available in The States tends to have salt, oil and sometimes sugar added to it, whereas in Europe it tends to be just ground roasted peanuts with no additives. Personally, I have come to prefer the kind with no added ingredients.
My nut butter of choice is raw almond butter, but it can be pricey. The best deal I have found is at Trader Joe's, which sells it for $4.99 for a standard sized jar. Most health food stores charge twice that.