Have not used them, but here are some others I found after a quick gander.
http://www.pccard.co.uk/support/pdata.php
http://www.amtron.com/price.htm scroll down to "PCI Bus Card Reader/Writer"
http://www.pcisystems.com/CARDBUS.html -not what you want but intresting stuff
http://www.synchrotech.com/products/card-rw_08.html

but given that a lot of the desktop wireless NICs are nothing more then a PCMCIA wireless NIC with an adapter you should have a few to choose from......I think....<insert confused smilie>