First and foremost for technical resources at the Sterrewacht is the Computer Group Documentation.
This is updated regularly by the IT staff here at the Sterrewacht and it contains everything you want to know including (but certainly not limited to) general observatory account information, known issues with current operating systems, customizing your account and email preferences, and managing your data on the network. Check it out for yourself, it's quite the wealth of IT knowledge.
For those just starting at the Sterrewacht, this subsection of the Computer Group Documentation has helpful lists of what is available on observatory computers (though the list is not complete). It provides introductions to various programming packages and languages including C, Fortran, Python, and IDL. Also particularly helpful is the Intro to UNIX section which explains the background of UNIX-based systems and explains how to get the most out of the C-shell installed at the Sterrewacht.
If you cannot find what you are looking for on the website, you can always submit a request for help or report an issue via the Helpdesk Form or visit the computer group in Room 408. The man in charge of the Computer Group is Erik Deul.