With a quick Google search I was able to find a couple of things which might meet your requirements.
Trouble Ticket Express – http://www.troubleticketexpress.com/
QuickIntranet – http://www.quickintranet.com/
Audit My Pc – http://www.auditmypc.com/help-desk-software.asp
Universal FAQ Manager – http://www.universalfaqmanager.com/
For all of these you will need some sort of computer to act as the server for the system.