If you have not read the work of James Branch Cabell, where would you start? I began with The Cream of the Jest: A Comedy of Evasion, when I was 17. I have no regrets. But I do not think there is any question about the ideal Cabell starter: The Music from Behind the Moon: An Epitome, from The Witch Woman (1948).*
But after that, what?
Well, it depends.
I have a go at a decision tree — hey, it branches! — to aid the curious reader:
* The first printing of the story was as a large, stand-alone illustrated book published by the John Day Company in 1926. It is a lovely edition, but the final printing in The Witch Woman was the final revision of the story, and it is the best. Read that version.