It probably doesn't exist...
Manufacturers usually do not provide WinCE drivers for USB devices. And since this is a "g" adapter, there's even less chance of a generic driver.
It's better for you to get a CF or 16-bit PC Card adapter that is compatible. Check the hardware compatibility library on this site.
If you must use the USB port for wireless, I'm afraid it's not easy, but slightly possible. I've heard one
(and only one
) report that a very specific USB wireless b adapter works with reference drivers
(that normally only developers can get
) on a Pocket PC. Here's the whole story:
http://discussion.brighthand.com/showthread.php?s=&threadid=113899