Here is a good book, that's out of print
Teutonic Myth and Legend
This is Donald Mackenzie's able retelling of the Northern mythological cycle. He weaves a coherent narrative from the Eddas, the Niebelunglied, the Volsung Saga, Beowulf, the primordial Hamlet myths, and Medieval German tales of chivalry.
Also The Story of Siegfried
This is a good Irish legend The Boys' Cuculain
It is not as well know as many other popular European myths.