I purchased a D-Link DWL-G122 802.11g USB Adapter to use with my Mandriva Linux based router and was pleased to find that it worked out of the box. (I was also pleased to find a desk dock for USB sticks included in the box.) Mandriva installed a wireless Ethernet device named "rausb0" which worked just as well as my standard eth2 (built in mini-pci prism card). I verified that the network connection worked with both an access point (managed) network and an ad-hoc network.

Another adapter I bought, the IOGear GWU523 was identified and loaded out of the box on Ubuntu, but not on Mandriva. When I plugged it in the zd1211rw driver recognized it and gave an error: " zd1211rw 4-3:1.0: couldn't load firmware. Error number -2" and "Cannot find  firmware file 'zd1211/zd1211b_ub'" error messages.

I did a urpmi zd1211 and it grabbed and installed the following two RPM's: dkms-zd1211-2.5.0.0-0.r67.1mdv2007.0.i586.rpm and zd1211-2.5.0.0-0.r67.1mdv2007.0.i586.rpm
Because this is a dynamic kernel module, it rebuilt the module during the install, which took a few minutes.  However, the firmware file was still not to be found.

The  driver website, http://zd1211.ath.cx/wiki/DriverRewrite, has good information, including a download link to the firmware files that I needed.  This got my device to show up. HOWEVER, even after it appeared (as eth3) I was never able to get it to connect to the two networks in the house (one managed access point, and one ad-hoc). So, I recommend against the IOGear GWU523 for use with linux.