For good, solid info with a definit slant towards gaming, here are two of the best sites I know of.
The first one is the original website for Cutting Edge Miniatures. At the left of the page click on the various links and you will get basic, historical info. The historical info provided is really good.
https://cuttingedgeminiatures.com/This next one is similar but includes lots of gaming pics, some rules and some painting tips.
http://sumer2sargon.blogspot.com/p/history.htmlAgain, check out all the tabs to the right.
The next two are sites are dedicated to the history or Mesopotamia.
http://sumerianshakespeare.com/https://allmesopotamia.wordpress.com/There are few other websites out there with some really awesome Mesopotamian wargaming info and pics, mainly centered around Warhammer Historics.
I would also recommend the following books, but there are gobs of them out there!
"The art of warfare in Biblical lands: In the light of archaeological study" by Yigael Yadin. It is dated but filled with tons of pictures.
"Warfare in the Ancient Near East 10 1600 BC" by William J. Hamblin.