Here is the amazon.com listing for the hardcover edition (with all of the beautiful illustrations). There is a paperback edition, but I think it lacks the illustrations; part of what "makes" the book.
EXCERPT from "The Most Beautiful Player of All":
But then Thespia realized that a light was shining in the darkened auditorium. The man she had seen in the gallery shadow seemed to be standing in his own light. She gasped and took a closer look; he seemed vaguely familiar. From the back of the hall, he raised his hand in greeting. Slowly, hardly realizing she did so, she reached out her hand toward him.
And the theater quieted as all watched the man walk within a center of radiance to the orchestra pit. He perched upon the rim, apologized to the musicians, and vaulted up onto the stage. "This is where I make my entrance, I believe," he said, and his voice was wonderful, filled with the echo of faraway hills and laughing country streams.
He stood in the middle of the stage and held out strong arms. "There is a real kingdom," he announced, "and a real king."