CounterStrike and Garys Mod

Hey ATS, anybody play garysmod or counterstrike? I am trying to set up my own server but I am having a problem with mac as it requires a command line script for Xcode which I am also going to be learning to do to create some apps for the iPhone. Could anybody help me out here?

"Xcode is not installed, or was installed with UNIX Development (10.5+) or Command Line Support (10.4) deselected."

Also if you all are interested in playing some CS let me know. I get discouraged from playing on other servers cause I am very new to counterstrike and do not tend to stay alive very long with those who play 24/7.