these places are usually hush hush you usually find this out when watching people like celebrity chefs and Ray Mears when they are looking for them.They usually do not like people (joe public)hunting for truffles.
But they are in the UK

needle and haystack spring to mind,if you go hunting and find any then let us know,we promise not to tell.....but on a serious note like hijuju says the uk has them but only in afew places.