A lot of these books are expensive. They are mainly used for academic purposes, not for use by the general public.
You won't find Sitchen or the Necronomicon here, sorry, I deal with reality as often as possible.
A few of these books are Ugaritic/Canaanite, not properly Sumerian or Babylonian; I happen to like Asherah.
The book called The Image of the Netherworld in Sumerian Sources is included because it is nearly impossible to find a book on that subject.
I did catch a major error in it, but otherwise I recommend waiting on that one until you are familiar with the mythology.
-Michele
Inanna by Diane Wolkstein and Samuel Noah Kramer
Mesopotamia by Gwendolyn Leick
Prophecy in Its Ancient Near Eastern Context by Martti Nissinen
The Legacy of Mesopotamia by A. T. Reyes
Desire, Discord and Death by Neal H. Walls
The Serpent Symbol in the Ancient Near East by Leslie S. Wilson
The Babylonian Gilgamesh Epic by A. R. George
Noah's Ark and the Ziusudra Epic by Robert M. Best
Myths of Enki, the Crafty God by Samuel Noah Kramer
Sumerian Mythology by Samuel Noah Kramer
Ancient Near Eastern Texts Relating to the Old Testament by James Bennett Pritchard
Creation Stories of the Middle East by Ewa Wasilewska
History Begins at Sumer by Samuel Noah Kramer
Enuma Elish Vol 1 & 2 by Leonard W. King
The Hebrew Goddess by Raphael Patai
The Cult of Asherah in Ancient Israel by Judith M. Hadley
Goddesses and Trees, New Moon and Yaweh by Othmar Keel
Women in the Ancient Near East by Arthur Frederick Ide
The Image of the Netherworld in the Sumerian Sources by Dina Katz
Religion in Ancient Mesopotamia by Jean Bottero
Gods , Demons and Symbols of AncientMesopotamia by Jeremy Black
The Harps That Once . . . by Thorkild Jacobsen
Mesopotamian Witchcraft by Tzvi Abusch