From 1812 to 1816, folklorist T. Crofton Croker roamed southern Ireland, listening to stories of changelings, pixies, and other supernatural creatures. His collection of folktales, recounted in plain but colorful language, was an overnight bestseller. This edition of Croker's ever-popular compilation is illustrated with scores of winsome engravings. Reprint of Fairy Legends and Traditions of the South of Ireland, originally published by W. Swan Sonnenschein & Co., London, 1882.
Here's a sample of other books in this Dover category
Celtic Myths and Legends by T. W. Rolleston Masterful retelling of Irish and Welsh stories and tales, including Cuchulain, King Arthur, Deirdre, the Grail, and many more. First paperback edition. 58 full-page illustrations and 18 figures.
Celtic Gods and Heroes by Marie-Louise Sjoestedt Noted French scholar and linguist discusses gods of the continental Celts, beginnings of mythology in Ireland, Irish mother-goddesses and chieftain-gods, and heroes.
Celtic Fairy Tales by Joseph Jacobs Great folklorist's selection of the finest legendary and folk material from Welsh, Scottish, and Irish sources. 26 medieval and modern stories in all. 46 illustrations.