I started with the one by Eric Evans, and I think is an amazing book. You could start with that and I think you will be fine. But before that, I think it would help to read Enterprise Integration Patterns by Fowler. Also, Agile Software Development: Principles, Patterns, and Practices. It is a lot more productive to start with PPP, because the concepts in that book are considered the baseline. And the book with Patterns integration scratches the surface for DDD, and is the first step into the concept of a domain model. It also has some important insights about when not to use DDD, and make use of other simpler patterns, on simpler projects.