Ok, if i'm understanding you correctly, you want to share that satellite connection with the rest of the network?
Simple enough.
First, you've got to realize that nics will be called Eth0, and Eth1. It depends on which driver is loaded first, as to which will be which.
Are they both the same type of card?
If they are, then the same driver will run each card and you'll have to do a little testing to figure out which is which.
Now, what you need to do is set up some routing tables that will let the networks talk to each other.
Do a search for routing tables, iptables, and check out
www.tldp.org for how-tos.
Good luck, hope i understood what you wanted