I believe you can do it in the registry... I've not tried it myself, so try this at your own risk!
To disable USB storage devices altogether, change the value of the Start key under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStor from 3 to 4. You can get a free
tool from IntelliAdmin to do it for you if you don't want to mess with the registry yourself.
To disable write access to the USB ports, and still have them available for read access, add a DWORD key called WriteProtect under HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\StorageD evicePolicies, and set the value to 0 to disable write access, 1 to enable. Note that this may affect use of USB printers etc.
Not sure about any PCMCIA based devices though... perhaps you could disable the controller in Device Manager.
I haven't read your previous topic, so this may have been covered already, but make sure users can't transfer the information you want to protect by other methods such as internet (bearing in mind it may be disguised when transfered), or bluetooth.
Hope that helps.