You need to get an LC ethernet card (by Farallon or Asante) from one of the major vendors or you can get a used card. It is supposed to come with drivers. You need one that has an RJ-45 connector (10baseT) and you can connect that to a hub using a patch cable. To connect directly to the mother machine, you can use a cross-over cable, but they are not as reliable as using even a cheapo 10baseT hub.
Some of the older RJ-45 cards might be 2baseT, but I think that will work with a 10baseT hub.
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