What you need!
Option 1:
2 x 10/100 network interface cards (NIC's). Brand is not that important.
Enough networking cable, aka CAT5 (category 5) to reach from one computer to the other
Either Windows ME, Windows 98 second edition or Windows 2000 on both computers or a software package like...
If you can connect the computers together with a network cable (the most economical and functional alternative) it's not hard. There are "modem sharing" packages you can buy and it handles the internet connection part (basically detects when the Internet connection is needed and connects...