Is it only available as an eBook?
Although eBook versions of my own books sell almost as many copies as printed versions, personally I just cannot warm to the medium. For me a book has to be something that I can pick up, carry round, place on the shelf, scribble in the margins, read in the loo, etc., etc. I most certainly don't want a reference book that I have to view on a computer monitor or tablet.
I searched for "Landscapes in Lightroom 5" on Amazon.co.uk without any success.