Title: Howl's Moving Castle
Author: Diana Wynne Jones
What it's about: Sophie Hatter is the eldest of three sisters, and because of this, she is destined to fail. Why? Haven't you ever read fairy tales? It's always the youngest who ends up succeeding. Anyway, Sophie has resigned herself to a boring life working in the family hat shop. This is all mucked up, though, when the Witch of the Waste comes into the shop one day and casts a curse on Sophie, turning her into an old woman. Sophie, quite normally, doesn't want to be seen like this, so she sets off and tries to find a way to break the curse. She soon stumbles upon the moving castle of the Wizard Howl, and she sets herself up as Howl's housekeeper while still trying to figure out a way out of her curse.
What I thought: Plenty of magic and humor and interesting characters, all of which are to be expected from Ms. Jones, who is probably the best fantasy author ever, in my opinion. Sophie is an interesting and sympathetic main character, and this book is a funny one. It's pretty hard to say what it is that makes Diana Wynne Jones' books so amazing, but whatever that quality is, Howl's Moving Castle definitely has it.
Overall: Very fun and worth reading.
As a side note, the film version is also worth looking into. I actually saw that first. Both versions are very good, and they differ from each other so that they tell slightly different stories. Miyazaki films are always good, and when the story being told is one of Diana Wynne Jones', well, you just get something exceptional.