The Edda (also known as the Prose Edda or Younger Edda) is one of the best and most complete sources of Norse myths.
Written in the early 1200s by Snorri Sturluson, an Icelandic scholar and Christian, it is where we get the majority of our modern knowledge of Odin, Thor, Loki, and the other mysterious elements of Norse beliefs like the ash-tree, Asgard, and the Bifrost. If you're wondering who or where Marvel got the idea of Thor, start with the Prose Edda. Or if you've watched the History channel's "Vikings" and are wondering, how do we know all this stuff about the Vikings? Start with the Prose Edda. If you're a big fan of J.R.R. Tolkien's books and want to know what fueled his imagination, start with the Prose Edda.
This edition is an easy to read translation with a helpful introduction and notes that will guide your reading of this remarkable book.