the way i did it before was using a crossover cable between the 2 PCs. In your IP settings, you'll want to make the IP addresses similar.
Example:
PC1: IP = 192.168.0.4
PC2: IP = 192.168.0.5
both would have a subnet mask of: 255.255.255.0
Right Click My Computer, hit properties, and network identification. Click the properties button and make them both have the same workgroup
You'll have to set up shares on these computers too.
That's the jist, but I'm sure there'll be better advice to follow