Make sure that both computers have Client for MS win installed, File and Print Sharing installed, and a common protocol (be it NetBeui or TCP/IP). You can do that via network properties.
Now go to printer properties on the PC with the printer, and share it. Note the name of this PC and the name you give the printer. You'll need it for the other computer.
On the other computer, when you're installing the printer, tell it your printer is networked. The address of the printer is now //computername/printername
Once it detects the printer, install the drivers, and you've successfully networked a printer.