Fortunately or unfortunately a cisco configuration is not a point and shot gui wizard stuff. That's why you can make so much more with a cisco router than a gui/box router. Because of this a broader knowledge is required to configure a cisco router. I assumed you know how to configure a Cisco router, at least the basic's - maybe there is Windows based configuration wizard, which can do the basics, then additionally you'd just need to add the secondary addresses, enable nat and add the port forward commands.
A basic config is pretty much seen at
http://www.verio.com/support/documents/view_article.cfm?doc_id=506additionally you'd need to configure the "wan" addresses [serial0 here, I cannot know what you have, nor the netmask, nor the "rest"...], so your final WAN interface config could look like:
interface Serial0
description Your Company Name
encapsulation ppp
ip address 72.36.99.1 255.255.255.0
ip address 72.36.99.5 255.255.255.0 secondary
ip address 72.36.99.7 255.255.255.0 secondary
and I guess, in the global config the:
ip nat inside source static 192.168.1.102 72.36.99.1
ip nat inside source static 192.168.1.103 72.36.99.5
ip nat inside source static 192.168.1.104 72.36.99.7
[though i'm not sure about the proper inside/outside syntax/usage, my definitely working configs are not at hand now, so it is a starter anyway...]
If it is still not enough, I suggest to post further questions in the networking/router section
(
http://www.experts-exchange.com/Networking/Networking_Hardware/Routers/#browseZones )
and I also recommend raising the points...