These are the books that I've read so far that I feel made the best impression on me, that is relevant to Laravel and PHP/Programming in general. Even though the two Laravel books are "dated" since they are for version 4.1 there are still a lot of things that can be learned from them.
"I found this book to be a great mix of solid advice and wonderful analogies!" --Martin Fowler, author of Refactoring and UML Distilled
The Laravel (v4) handbook. Also the humer is top notch!
If you've already built a few things in Laravel and you need to start thinking about architecture, this is the (Laravel 4) book.
Very nice book that starts pretty basic for PHP but then builds up for design patterns.