The slot used by Cardbus cards is just a PCMCIA card slot which supports the Cardbus interface. What you need to know is whether the PCMCIA slot on your laptop supports Cardbus.
Go to Device Manager in Windows and expand the PCMCIA sockets/adapters category. If you see a reference to Cardbus, then you have a slot which supports Cardbus. If it lists only PC Card, then the slot does not support Cardbus.
Laptops released in the last 3 or 4 years usually support Cardbus.
PCMCIA types I, II and III refer to the thickness of the cards/slots. Type III is the thickest. To use a particular type of PCMCIA card, the slot must be of that type or a later type (so e.g. a type II card can fit into a type II or type III slot, but will not into a type I slot).