Just to echo what suthercd said, you need the full Developer Tools CD, the August Update is just that -- an Update.
If you're in the US, you can walk into an Apple store and get the folks at the Genius Bar to burn them for you, if you buy Mac OS X then you get the CD in the box, if you bought a new Mac then you have the CD image in /Applications/Installers, and you can order them for $20 S&H from the ADC site IIRC.