For an overview of PSA and commands, see VMware vSphere 4.1 PSA.
Also see the vSphere CLI guide, vSphere Command-Line Interface Installation and Reference Guide.
Michael is a Senior Consultant for Xtravirt. If it's got buttons or flashy lights on it then it'll probably be on his radar. When not "mending computers" (it's sometimes easier than explaining "cloud" to relatives), Michael provides essential education, entertainment and trampoline services to his two children.