splitting hairs again, only peripherals that comply with industry standards do not need special drivers. the internal bluetooth adapter connects via usb, it shows up as a standard human interface device (hid), there are drivers already built into osx, and the apple adapter is really a d-link in drag anyway. that is why the external ones work fine.

the 802.11 usb adapters do require additional drivers, and most do not have mac support.

if one is set on using an external 802.11b/g add-on, then the best choice is a wireless ethernet bridge, such as the linksys wet-11. it will work on anything with an ethernet port. however, they are generally more expensive than the internal apple airport card.

airport is just apple's name for 802.11, so whether you get the internal airport card or an external solution, it will connect with any 802.11b/g base station, either apple's or third party. there may be a slight issue with using passphrases (i.e. wep key conversions vary across different vendors), but that is about the extent of it.