HI there,
there u go. But u shold read some books for that. Networks arent so easy if u dont folow me 
1. One IP from ur ISP1 NIC + 1 MODEM on the first PC
1 NIC on the other and each other
conection as folow:
internet----MODEM set as ISP require. U need PROXY AND FIREWALL SOFTWARE. Set the NIC to have addy as 192.168.xxx.xxx. The Proxy is giving internal IP's for THE REST OF THE COMPUTERS. Plug as many PC's as u can buy or ur proxy alawed to the HUB.
IF U USE TCP/IP PROTOCOL ON THE PC's UR NETWORK WILL BE ACCESABLE FROM THE NET IN THIS CASE. U WILL NEED FIREWALL ON EACH PC IF U SET SHARES. Remove the NETBIOS protocol, it is not safe.
THEN USE TWISTED PAIR CAT-5 TO CONNECT COMPUTER TO HUB OR TO SWITCH, USE STRIGHT TO CONNECT TWO SWITCHES OR HUB TO SWITCH, HUB TO HUB AND SO.
Connecting HUB to SWITCH: HUB's Uplink to the next regular by twisted.
hubs regular link to the next hub's regular with stright thru cable.
see the difference? hubs and switches has button on their uplink so u will never have it wrong.
For software go to: http://www.sygate.com
To test Ur PC SECURITY go to: https://grc.com/x/ne.dll?bh0bkyd2
sam
:p