INTERNET CONNECTION

I HAVE THREE PC WORKSTATIONS BOTH OF THEM ARE WINDOWS98 SE AND ALSO HAVE ONE PC SERVER. (WINDOWS 2000 SERVER). SERVE AS A SERVER.AND I USE 8PORTS SWITCH.MY PROBLEM IS HOW TO CONNECT TO THE INTERNET USING 56K MODEM INTERNAL.AND ALSO THE WORKSTATIONS CAN ACCESS TO THE INTERNET.PLEASE GIVE ME THE INSTRUCTIONS STEP BY STEP. OR WHITE PAPER. THANKS A LOT..