hi,
in a nutshell:
i installed AsteriskNOW with FreePBX, and i dont know how to set up a service number, wich, if called, to a certain group of Telefones. Much like a mini ACD Server. Since i am from germany and english is not my native language, i have no idea what this is called. maybe Service Number? or Routinggroup?
long version:
Hallo. I am Ole, and i am new here. I am a Trainee in an IT Department. I am currently working on a Project to change our Office Phone System.
I stumbled uppon Asterisk (of course) and that lead me to FreePBX. I installed AsteriskNOW on an isolated Network, with an DHCP Server, one client PC and three “Siemens Openstage 60” VoIP Phones. Everything worked fine pretty quicky. i added three extensions and got the phones and the server connected. they can call, and redirect. its great. 
Now for our IT department, we have an internal Hotline. And it automaticly redirects the call to one of our office Phones. i bet this is very easy, but since i am very new to the whole VoIP-SIP-Gateway-trunk-extension-holymoly, i could realy use someone to send me in the right direction.
Thanks upfront for the help!
ciao
Ole