SharePoint STSADM Command Line Reference
Because I usually can’t find these details when I look for them, I thought I’d post the links. Note that if you go to the top level reference page for STSADM at http://technet.microsoft.com/en-us/library/cc261956.aspx, not all of the commands are listed (e.g., Adduser), whereas the links below seem to contain everything, including operations that were added as part of SP1.
STSADM Operations: http://technet.microsoft.com/en-us/library/cc262643.aspx
STSADM Properties: http://technet.microsoft.com/en-us/library/cc263358.aspx