Teddy, there are dozens of such books, on both the Windsors and other topics regarding royalty. Just 3 on the D&D of Windsor are THE WINDOSR STYLE- Suzy Menkes, THE PRIVATE WORLD OF THE D&D OF WINDSOR- Hugo Vickers & THE JEWELS OF THE DUCHESS OF WINDSOR-Culme & Rayner.
There are several on the others, particularly a glut of them on the late Diana, Princess of Wales and not a few from the recent Jubilee of the Queen.
Books on the continental royals, both collectively and individual families, books on palaces, jewels and heraldry & genealogy.
Robert Golden has a nice series of "small" coffe table picture books, as does William Mead Lalor [Royaly before, between and after the wars]
There are some lavish books on the Indian and Asian monarchies. And the Ottoman and Pahlavis dynasties as well !
Several auction catalogues serve quite well as coffee table books- Windsor, Hannover, Princess Margaret, etc.
If you have any in particular you are interested in, let me know and I can tell you what I have. Also Arturo has a great selection of such books
I am sure this thread will build up quite a list in itself !
Cheers,
Robert