Start with high-confidence arthurian tales books, then narrow by subgenre or adjacent topics.
Otherworld Chronicles #3: the Dragon King
Nils Johnson-Shelton
Tristan and Lancelot: a Tale of Two Knights
James Persichetti, L.S. Biehler
The Squire's Quest
Gerald Morris
Merlin's Harp
Anne Crompton, Anne Eliot Crompton
The Little Duke
Charlotte Mary Yonge
The King of Elfland's Daughter
Lord Dunsany
Arthurian Myths & Legends
J.K. Jackson, Prof Raluca Radulescu
The Red Keep
Allen French, Andrew Wyeth
