From Vicki Steward’s blog Normal For Glastonbury: Life in the Oddest Town in England, a list of all the novels set in Glastonbury.
There some Phil Rickman titles there that I had missed, possibly because they were categorized as YA and published under a different name.
Marion Zimmer Bradley, of course, Faye Weldon, and lots of others. And the heavyweight, John Cowper Powys’ A Glastonbury Romance. Unlike Vicki Steward, I have read it. It is odd and complex, but so was he.