Need to configure server for software purpose, ICS and NAT

Hello
We have recently opened our new warehouse for automobile spares.

I have one server for which I want to connect as main for software purpose (need to connect wings software directly to access from head office as client). The server running Windows Server 2003 and have two network cards and I have static IP to connect to network.

I want to make Server as Main following the static IP to configure in it and want to share Internet connection to all LAN computers. I have DLINK access point.
Example::

Internet
I
I
Server (Main)
I
I
DLink Accesspoint
I
I
I
Clients

I need help and step by step help would be preferable to make myself understand better.

Thank you very much
Zubair