Kokugakuin University has your back. The Encyclopedia of Shinto is a remarkable resource, especially for one that's given away free, and there are some fascinating papers elsewhere in there.

But there is also much evidence that sun deities other than Amaterasu were worshiped. In the section of the Engishiki known as the "directory of names of kami" (Jinmyôchô), shrines with names like "Amateru-mitama Jinja" and dedicated to a variety of sun-deity were found throughout the capital region. Some commentators also hold the view that at the stage before Amaterasu became the imperial ancestral deity, the male solar deity Takamimusubi had that role, but that for a variety of reasons, he passed that status to the goddess Amaterasu.

Now that I did not know. But Joseph Campbell would be relieved to hear it.