Here’s a quick list of recommended reading for anyone interested in Mac OS X development and software development in general:
THE book everyone recommends (as well as myself) to start developing for Mac OS X. Very comprehensive. You can read this from cover to cover easily, and you’ll have fun doing it. This is a tutorial-style book with concrete examples demonstrating each concept. The book is a great introduction to the world of Cocoa programming and enables you to begin developing your own apps for the platform.
Required skill level: Beginner
A great book that goes more in depth on the design patterns and concepts behind the Cocoa frameworks. Required reading for anyone who wants to master Cocoa. You will have some “aaah!” moments when you realize how the patterns help Cocoa do it’s magic. Easy to read from cover to cover, but it’s also a great reference.
Required skill level: Intermediate
Programming philosophy and self-discipline, if you will. It does contain quite a few code samples to demonstrate various recommended techniques, so it’s not only philosophy. This book contains a lot of very good advice for software development and everything related. Also a must-read, particularly for someone with little software development background.
Required skill level: Beginner / Intermediate