justin,
i have used the hawking hwug1 w/kismet in linux, a pigtail, and a 5 dBi mag mount omni antenna
http://www.fab-corp.com/product.php?pro ... 282&page=1 which works really well.
do yourself a favor: download backtrack3, boot your laptop off of it (check HCL to make sure it is compatible or d/l and run the vmware version), and run the passive sniffer kismet. you will start learning an OS other than windows -and- you will not be advertising your presence like you do with netstumbler!