An introduction to the Stealth project, including what will be covered in the tutorial episodes.
The tutorial videos are available here:
There's a support thread for upgrading the project to Unity 5.x here which is probably of interest no matter what version of Unity you want to upgrade it to:
Also, I made an extended version of this project, available here:
Disclaimer: This project is no longer officially supported. Most likely you'll get no support from me either, just use take it for what it is.
The Unity project is hosted on Github
You can get Unity 4.7.2 for both Windows and Mac from here:
Unity download archive