I've checked this out of my library a few times and finally read it in May. This is one case where I'd say the film definitely outshines the book. The book is enjoyable on its own, but if you can't find a copy I'd say you're not missing much. It's sweet but nothing life changing.
I picked it up totally because of Hayao Miyazaki. A cute and light-heart story, no harm for children. A bit too young for me but it made me feel happy while reading.