As well as being on Amazon UK and Amazon.com (and Amazon Spain, France, Germany and Italy) in both paperback and kindle versions, it's also now on the following too.
Smashwords - in a host of ebook formats
Barnes and Noble in Nook ebook format and paperback too
Diesel Books - in paperback
Kobo for the Kobo reader
WH Smith - for UK Kobo readers
and in a short period of time, you should see it on iTunes and the Sony Reader store too!
And of course, my original book is available in the same places.