The Complete Gods and Goddesses of Ancient Egypt by Richard H. Wilkinson

A complete sampling, perhaps. As the text admits, it's impossible to get them all. Not at all helped by the way they were "rich in names" and also the syncretism that lumped many of them into a single god.

Concepts of the gods -- such as their being mysterious in form despite the many depictions of them, the various incompatible cosmological myths, religious practices, relationship to the king -- and then a long listing of the known gods. Organized by the form they were most depicted in, such as anthropomorphic, or avian, etc.