[itsm] Where to start ?

Hi, I've been searching about for an open source cmdb for a while, and I'm also looking to switch to a decent helpdesk/ticketing system. I've been playing with OTRS for a few weeks and then I see ITSM is released. Great, I'm keen to get started. Where do I start ? Do I define locations first, or services, or computers and hardware ? It would seem that getting it wrong during design will be something I'll regret. I need OTRS right now, so I can't wait to learn the nuances of ITSM. If I deploy OTRS and research ITSM on a separate system, will I be able to add my ITSM to my existing OSTR later ? Can anyone offer some advice ? Thanks Matthew Joyce 02 9382 0051 | IT Manager | Children's Cancer Institute Australia for Medical Research