I found a handy list of Croatia-related books on Amazon today. A comprehensive view overall, covering aspects of history, culture, language and tourism. A good starting point for anyone interested in learning more about this country.
Of all the books listed, the one I can recommend most highly is Croatia: A Nation Forged In War, by Marcus Tanner. A well-researched, in-depth look at the development of Croatia over the course of the centuries. Perfect for gaining a historical perspective and understanding the influences that are at play there.