Mac OS X is *NOT* Linux. Just as Linux is not Solaris, and Linux is not AIX, and Linux is not HP-UX, and Linux is not a whole bunch of other Unix distributions. Especially when it comes to administration. Every last one of these operating system do something (or a lot of things) different on the Admin front.
When it comes to commands and utilities, Mac OS X leans towards the BSD flavors vs the GNU flavors favored by Linux. A lot of this revolves around GNU's use of the GNU Public License v3 which is very restrictive to commercial companies such as Apple.
You are of course welcome to download many Open Source projects, compile them (assuming you have first installed XCode developer tools), and install any commands & utilities you prefer over the Mac OS X shipped versions. NOTE: I would NOT replace any Mac OS X provided commands & utilties, but rather make sure you install them in /usr/local/bin, or some other place different from the Apple provided command. Changing an Apple provided command or utility may cause dependent Mac OS X scripts to fail, so you do not want your versions in the default PATH.
There are also 2 package managers available for Mac OS X:
MacPorts
<http://www.macports.org/>
Fink
<http://www.finkproject.org/>
Although sometimes you get more than you expected with the managers.
And besides the Developer forums, you might also consider the Mac OS X Technologies forum, which often deals with command line issues.
There are also a few books on the Mac OS X command line environment. While some of these mention Tiger, Leopard, Snow Leopard as the Mac OS X version they were written for, in most cases the command line environment is still the same, or has not changed all that much.
Also Google can be your friend in finding command line ways to do Mac OS X things.
Finally check out MacOSXHints.com as there have been many postings there on using the Mac OS X Unix side.
Message was edited by: BobHarris