Not sure where in the UK you live but there's a small camera shop (London Camera Exchange
*) in Colchester that regularly seems to get stock of the 18-200mm VR. I walked in and they just had one and from what the guys in the shop were saying they get a regular order every couple of months. I don't know if they have one at the moment but if you're not too far away it might be worth a trip if you're interested.
*Address and phone number are a little further down on that page.
I am in Dorset - my local shop says they now don't have a great problem getting these - I am 1st on their list and they even sell it £50 off list price, so I keeping my fingers crossed. I want it within 2 weeks or I will have a dilema whether to get another lens or go on holiday with my "happy snapper" again. They tell me this won't be a problem, but I am not so sure. I have a fall back of asking them to give me a used lens on sale or return for that holiday if they let me down (they might say no of course!)