From time to time there are books I hear about that are released in the UK, but not in the US. The expense to order them from amazon.co.uk is is pretty high due to the cost of shipping them across the Atlantic. I recently was introduced to The Book Depository. They offer free shipping to the US and many other places around the world.
Last week I ordered. The Blade Itself by Joe Abecrombie, Winterbirth by Brian Ruckley, and Dreamsongs by George R.R. Martin.
They showed up yesterday! One week after I ordered them. That is darn good service for an order within the US, much less all the way from England!
So if you are looking for a UK book give The Book Depository a shot.