I think this has been discussed before. A printed book is unavailable. It was only ever an ebook. Correct this if its wrong but I seem to recall that the author is apparently disinterested. I have a copy for which I would happily pay should those with copyright privilege choose to invoice me as a soft copy or I would upgrade to a hard copy if possible and reasonably priced.
The other alternative would be to simply delete it. I haven't actually cooked anything from it so I don't know if I'd choose to keep it.
The post in this thread by the author appears to grant permission to use the ebook and he wishes people luck in cooking from it. Martinwhynot claims to be the author with contributions from Alex Wilkie.