nowhere to put it? Is this a PCMCIA card(PC card) ? If it is, it will be a rectangular flat card, it fits into a PCMCIA slot, usually located on either the right or left side of the system and the slots may have filler cards in them(this is a plastic dummy card to fill the slot to keep dust and trash out when not being used)
Also, as YnW stated, you'll need a wireless g router/access point. I'd recommend getting the same brand as your card to avoid any conflicts with drivers or firmware. It will also help if you ever need to contact the manufacturer for warranty or other questions. If you have several different manufacturers' equipment, each one will tell you to call the other guy.