In the tutorial series that these files are the source for, follow along with Jonathan Williamson as he models a Porsche from start to finish.
Videos will be uploaded here: https://www.youtube.com/user/blendercookie
The first five parts were made with Blender 2.49, and the last four were made with 2.5, so the interface will be a bit different.
Files?
Isn't there meant to be more than one?