This is a few years old now, but Drew over at macresearch.org has provided a host of cocoa examples:
Author: Drew McCormack
Articles in this series include:
- Hello Brave New World
- Classy Cocoa
- Living Objects
- Good References
- It’s All in the Genes
- Jekyll and Hyde
- Into Xcode
- IB, Therefore I am
- MVC is not the ‘Motor Vehicle Commission’
- Popping Up All Over the Place
- The Value in Keys
- Observe and Learn
- In a Bind
- Beginning 3D Visualization
- Continuing 3D Visualization
- Finalizing 3D Visualization
- Representing Data in Tables
- Graphing Data with SM2DGraphView
- Telling Your Story with Narrative
- Python Scripters…Meet Cocoa
- Multi-threading Your App with NSOperation and NSOperationQueue
- Core Data Models
- iTunes-ifying Core Data Apps
- Core Animation First Steps
- Core Animation Layer Trees
- Parsing CSV Data
- Getting Closure with Objective-C
- Bonjour and How Do You Do?
- This is the Message
- Developing for iPhone
- All Aboard Grand Central
- The Physics of Sumos (A Flirtation with iPhone Game Development)
- 10 Uses for Blocks in C/Objective-C
- Scrapbook of an Advanced Core Animation View