asterisk users - Jul 2004 - Call Forwarding/Redirection?

Hi,
I'm new to Asterisk and have been wondering how Call Forwarding would
function
in Asterisk.

I am wanting to get an E1 Card for my Asterisk Box and to get 10 odd channels
enabled on the PRI along with a block of phone numbers.  The question is, what
is the best mechanism to allocate the individual phone numbers to the clients?

Would the call forwarding be based upon CalledStationID?

Cheers,
Sahil