If you ever run out of Ethernet port on a computer, you can buy an add on card that will fit into either a PCI-e port which is number 6 or 7, or a PCI card which will fit into number 8.
Ethernet LAN's have come a long way in recent years. To get the fastest connection, get what's called gigabit LAN or 10/100/1000 or the 10/100/1000/10000 which should be out in the next year or 2.
The easiest way to set up a LAN at home is with a router.
You can check our Linksys router setup page for more
information. All you need to do is setup the router once,
then plug in any devices you want on your network to make a stable
The other advantage is, if you ever change computers you don't have to set up the connection again.