IBM Developerworks has posted the third and final part of their Global Positioning System Tutorial. The sample code is in Java but the principals apply to the more common languages used in embedded and robotics applications as well. The tutorial covers both the collection of data from GPS devices and the use of the aquired data. A free registration with IBM Developerworks is required to view or download the articles. Here are direct links to Part 1, Part 2, and Part 3 of the series.