Here are some resources for learning Sumerian. I relied heavily on Foxvog's grammar for my understanding of Sumerian, however, Jagersma and Zolyomi also have useful grammars. There are some differences between between grammars, as elements of the language are still up for debate.
A folder of pdfs, if one prefers to "DIY" and not follow my lessons.Gilgamesh.ch is a website run by a certain Dr. Koch, and has a verb conjugator for Sumerian. It is a wonderful way to understand how Sumerian verbs work and I recommend you check that out.
ePSD is a Sumerian dictionary that presents cuneiform as .png images.
ePSD2 is a newer Sumerian dictionary that is constantly being updated. It uses unicode characters for cuneiform, so if you do not have a compatible font, be warned.