the quickest and easyest solution is to buy a router. Other solutions include setting up one of the computers as a router, and using the hub as connector between your computer and his.
I'm also trying to hook up my PCs to play wcIII, but I already have a router.
I'm actually trying to find a way to connect through VPN to use my own local network so that I won't have to go through B.Net. Anyone has suggestions on getting this to work. I've tried just about everything... still no luck. I'm not giving up though. I can see the machines connected to the same network, but no LAN game.