by Halo Quin
This is very much a Pagan book, but includes the original folktales of many Welsh legends. These were well-researched and it's good to find them collected in one place!
The first part goes through rituals and offerings, visualisation suggestions, that sort of thing. The second part is more what I expected, following through the tales and their relationships to history and belief in Wales. Sources are cited and there's a pronunciation guide at the end.
There's a heavy dose of the author's personal beliefs throughout, but the folktales are genuine and this would be a good reference for anyone interested in British folktales and legends.