There is curently no driver available for the tri-mode IBM or Intel cards. In fact, there are no 802.11g drivers at all, though there are rumors of a wrapper which has been ported to OS/2 to allow loading the Win32 driver (for the Atheros chipset, I believe).
Anyway, the best supported cards are the Cisco 340 & 350 PCMCIA, IBM High Rate (802.11b) PCMCIA and mPCI, and the Artem 802.11b PCMCIA cards.
Best sources of informtation are the OS/2 Wireless Users mailing list, hosted on my server (send an email to firstname.lastname@example.org with the words "subscribe os2-wireless_users" in the body; archives of the list are available at http://www.2rosenthals.com/lists/os2-wireless_users ) and the OS/2 Compatible Hardware List at http://www.os2warp.be.
Best of luck with your Wi-Fi venture, and drop us a note on the mailing list to let us know how you make out!
PS - Warpstock 2004 in Denver this past weekend was absolutely terrific. Next year, everyone involved with Wi-Fi on OS/2 should attend, and everyone who wants more information - hands on, in many cases, or straight from the developers' mouths - should attend.
Lewis G Rosenthal, CNA
Rosenthal & Rosenthal