I have installed Xcode from the Tool cd, I thought that would let me use gcc from the command line but I can\'t find it.
What am I missing
EDIT
You didn't check the box that says "UNIX Development Support"[1] (or possibly you unchecked it; I can't remember if it's on by default or not) when you did the install, so it didn't install the necessary symlinks and drivers in /usr/bin/.
Reinstall, and make sure to read the descriptions of the configuration options and select the ones that you need.
1: "Optional content to allow command-line development from the boot volume. Installs a duplicate of the GCC compiler and command line tools blah blah blah..."