Can’t speak for the quality of these books, but I figure that free books are free books and they are worth the read for anyone with an interest in mythology!
Note: All of these books are free as of this writing and most are public domain, but always double check the price before clicking to purchase.
- The Children of Odin The Book of Northern Myths
- Asgard Stories Tales from Norse Mythology
- Myths & Legends of the Celtic Race
- Viking Tales
- Myths and Folk Tales of Ireland
- Hero-Myths & Legends of the British Race
- Aw-Aw-Tam Indian Nights Being the myths and legends of the Pimas of Arizona
- Myths and Legends of the Sioux
- Myths and Legends of the Great Plains
- Myths and Legends of California and the Old Southwest
- American Hero-Myths: A Study in the Native Religions of the Western Continent
- Nights With Uncle Remus: Myths and Legends of the Old Plantation
- Myths of Babylonia and Assyria
- Myths and Legends of Ancient Greece and Rome
- Myths and Legends of China
- Curious Myths of the Middle Ages
- Bible Myths and their Parallels in other Religions: Being a Comparison of the Old and New Testament Myths and Miracles with those of the Heathen Nations … Considering also their Origin and Meaning
- Myths and Legends of All Nations: Famous Stories from the Greek, German, English, Spanish, Scandinavian, Danish, French, Russian, Bohemian, Italian and other sources
- A Book of Myths
- Myths That Every Child Should Know: A Selection Of The Classic Myths Of All Times For Young
- Famous Tales of Fact and Fancy: Myths and Legends of the Nations of the World Retold for Boys and Girls
EDIT: And for those of you that do not have a Kindle — THERE IS AN APP for that! You can get the Kindle app for ipod/iphone etc here, you can also get the program for PC here, and finally the one for Mac over here!