Commands

CD or DVD .dmg or folder converted to true ISO-9660 filesystem - Mac OS X Hints

http://www.macosxhints.com/comment.php?mode=view&cid=89782 how to create ISO images from command line on OS X

Unix Toolbox

http://cb.vu/unixtoolbox.xhtml awseme reference, any *nix sysadmin must bookmark it