Google SketchUp is a powerful 3 dimensional modeling tool that boasts comprehensiveness and versatility for the average, everyday user. Unlike some of its contemporaries, this program is very user friendly. Check out this tutorial and learn how to go about modeling a Tractor from start to finish in Google SketchUp 6. It is sped up so it takes only 8 minutes to watch, though the original model took about 65 minutes to complete! Feel free to pause at any juncture during the tutorial in case you didn't catch a particular detail.