hello! I'm in urgent need of a linux-compatible low-profile 802.11g pci card or usb drive for a small form factor computer of mines (those computers that lies flat on a desk with a monitor on top, cannot fit normal sized PCI cards) that desparately needs to get on the internet. Does anyone know where I can find such a device?

(Thinks: how would the manufacturer expect the user to add a nic?)

SFF-PC's are not designed to be very expandable. Though, usually, the pci-capable versions have an adapter allowing normal sized pci cards to sit parallel to the motherboard. (Depending on the configuration.) However, some are based of laptop technilogy - using mini-pci cards and pcmcia cards. Are you sure this isn't one of those?

Supported wireless - go for prism chipsets.
As usual - work out what is available, then look them up.

Sometimes this functionality is intended via usb...