Here is what I found on the www, for MiB USB:
http://www.gilandre.org/sla/rqg01.html
In general, make sure the "usb-storage" modules is uncommented in /etc/rc.d/rc.modules.
Plug-in your USB key disk in the USB port.
Check "dmesg" to see what is the device that has been attributed by the kernel to the USB key (for instance "/dev/sda1")
The USB key (used in the example above) should be mounted with the following command:
sudo mount -t vfat /dev/sda1/ /mnt/hd/
I suppose that this will work also for other USB key-disk made by other companies than MiB. But I am not 100% sure... =(
Hope this helps!