The harware you need for a wired LAN is simple
1. An ethernet hub
2. At least two(2) cat5 or cat6 cables
3. A network interface card (NIC) on each computer.
The following steps are for Windows XP:
Once you have those items, which can be obtained for under $100, you put and end of each cable into the hub and the other end into either computer. The RAJ45 jack for the cables looks like a large telephone jack located on the back of your NIC. You then need to configure the ip adresses on each computer. (If you are sharing an internet connection, you will lose connection with that the way i do it.) Run the home or office network setup wizard from you network connections or my network places screen on each computer. Select the other option when it asks about the internet connection. Then select the option that says that this computer belong to a network that does not have an internet connection. Leave the workgroup name as mshome for convience's sake and enable file and printer sharing. Let it perform the operation and restart your computer if it says to. Once windows says that the LAN is in the task bar (it will probably say that it has little or no connectivity), go into the properties of the LAN and scroll down until you see the Internet Protocol (TCP/IP). Click on this then click on Properties. Select the option to manually configure the ip address. Set each ip adress to whatever you want that is easy to remember. They are usually something like 192.168.0.1. Then set the other computer's address to an ip address with the same first 3 values such as 192.168.0.2 (they don't have to be consecutive). Then set the subnet mask to the same on each computer and none of the other things really matter if all you want is to play games. Once you have done that, apply those changes and go to the tab where the Internet protocol was listed among the other drivers. Click on install... and make sure all of the following are installed: file and printer sharing, client, network monitor driver, microsoft TCP/IP version 6.0, NWlink netBIOS, and NWlink IPX/XPS/netBIOS compatible transport protocol. Uninstal the packet scheduler and go over the advanced tab. Click on settings, and make sure that windows firewall is turned off. Close the properties window and see if the LAN is now connected (probably at 100mbps if that is the speed of your NICs). Try the game, and if one can't see the other's hosted game, try turning off any firewall and retry it. I'm not sure about others, but if you have norton internet security, configure your firewall to allow the ip addresses of the computers and make sure it is not blocking the game.