Sorry but learning in the USA is half the cost of the UK, simple as. I did my PPL in 2006 for £2995, including a night rating. I also did 27 hours extra flying, and including the flights there & back, food, beer, taxis & a £300 headset, etc etc I spent just under £6000. That's a hell of a saving on uk prices, and I had an excellent dedicated instructor , and a couple of excellent instructors who flew the odd hour as progress checkers.
The bulk of the PPL is about learning to operate the aircraft safley, and that can be done a lot quicker & cheaper in the US' than here! It also leaves you a lot of change to fly with UK instructors to get familiar with UK airspace etc