I actually own a Dlink DWL-G650 that I modified to accept an antenna (RF SMA connector). I use it on my Compaq M700 and it works quite well. If you want, I can email you some pictures of what needs to be done to modify the card. Be warned that you need to know how to solder "very" small components as you need to move one capacitor, and then add your cable.
But... if I were you, I would go with a USB adapter instead. Experiments with the USB adapter show it's just as good if not better for reception than either my DWL-G650 (laptop), or my DWL-G510 (PC). And yes, my USB adapter is also a D-link... DWL-G132.
The reason I use Dlink is because of the software. Its more user friendly when it comes to changing/selecting which ap to connect to. I tried using a Netgear adapter once and I was picking up all kind of aps in Starbucks and it wouldn't let me select which one to connect to. It just kept auto-selecting a channel of someone elses laptop nearby and stopped me from connecting to the actual Starbucks server.
In any case, check out USB adapters, and also this neat webpage >>>
http://www.usbwifi.orcon.net.nz/
Now I'm not saying to "smooch" off anyone, but it might come in handy for say... when you go camping or something!
makai
Hawaii born, living in California.
T41, T42, X31, X61S