by Nigel Pennick Nigel Pennick is well known and respected for his books on magic and folklore. This is a good book on Earth-based spirituality. It is not, as the title might suggest, about Elemental Spirits. The book is about natural magic, in his own words, "It is the power of everyday objects...
An interesting, scholarly overview of the pagan customs, rites and ceremonies of the northern Europeans (with a bit of stuff from the rest of Europe). This book is similar to the works of Claude Lecouteux, only in less detail.