The book's title says precisely what it is. It is not a listing of 'best' books on Japan, nor a catalog of what is currently available. Rather, it is a guide for serious amateurs, those who for reasons of sentiment or profit wish to discover collectors' items in the field.
Joseph Rogala, who has quite apparently spent much time on this annotated guide, says that he wished his selection to be rounded. Thus the number of academic-type books have been trimmed to those considered truly vintage, government publications have been kept to a minimum and books on Buddhism have been selective.
Indeed, selective would be a way to describe this listing. William Plomer is represented only by his short story collection "Paper Houses," and his equally collectible novel, "Sado," is neglected. For Pierre Loti we are asked to look only for "Madame Chrsysnatheme," though the English translations of "Japoneries d'automne" and "La troisieme jeunesse de Madame Prune" are even more attractive if rarity is a criterion and the choice has been limited to "those unusual enough to warrant enclosure."