Japan’s national public broadcaster, NHK, has offered folktale translations via website and radio broadcast which are now a book: Once Upon a Time in Japan. This book was translated by Roger Pulvers and Juliet Winters Carpenter, using scripts compiled by the NHK World Radio Japan English Section. A review appears here at BookDragon, a blog of the Smithsonian Asian Pacific American Center.
BookDragon’s Japan page also lists other Japanese books in English translation. Well worth a look!