Hi Not Long Here,
Kindle is available to users of Amazon sites, but you'll only be able to order it if you live (or your IP is registered) in the territory where it's being sold. UK users will be able to buy it from Amazon.co.uk, but visitors from overseas won't. They'll need to go to their usual Amazon site. In many cases that's Amazon.com, and the book is listed there:
The Kindle version is also listed on Amazon sites for France, Germany and Japan.
Non-Kindle users can purchase the ebook for a wide variety of ereading devices including B&N Nook, WHSmith Kobo.
I hope that helps!
Helen