Terminal Services – can’t get users to log on

Hi all. I’m a proper newbie and have just set up 2 servers:
1x W2K3 SBS Standard as the main server
1x W2K3 Standard as a terminal server
(This is a configuration advised to us by the developers of the database package we are using.)

I seem to have both servers talking to each other quite happily. I’ve set up all my users and given them the necessary permissions (as far as I can see).
We are operating from two offices and I need 3 people in the satellite office to connect by remote desktop.

The bit where I’m stumped (for now at least!) is ascertaining what IP address to give to my colleagues in order for them to connect. Can anyone offer any assistance in this respect?
Cheers
R