If it has built-in wireless it won't have a port for it - it's wireless. It may have a physical switch though. (Look in the handbook.)
Assumnig XP go to Start, Show all Connections. If there is a wireless icon start it there.
If you do not have wireless built-in then you need to buy a wireless PC Card (sometimes called a PCMCIA Card.) and fit it to one of your PC Card slots.
t, August 2007