The Homeward Bounders. Jamie becomes a pawn in a game played by a mysterious and powerful group, and is repeatedly catapulted through space and time - always hoping to get home. Jones, Diana Wynne. Howl's Moving Castle. In the land of Ingary, such things as spells, invisible cloaks, and seven league boots are everyday things.
Nothing is quite what it seems to be.
Jones, Diana Wynne. The Lives of Christopher Chant. Christopher discovers that his dreams are so realistic that he can actually visit other worlds and bring things back from them for his beloved, yet mysterious, uncle. Jones, Diana Wynne. A Tale of Time City.