You can find the instructions for creating this sample here:
How to Add GPS to Your iOS App – Part 1
Shawn Grimes is a mobile app developer for ELC Technologies. He is a co-author of the book, iOS 5 Recipes: A Problem-Solution Approach (Recipes Apress). You can follow him on twitter @shawng. Shawn also works with high school students to teach them app development skills through the APPlied Club Program.