it probably already has.
just mount it.
after plugging in the usb driver, run dmesg, on the last few lines should be some note about a new usb drive being attached.
if this is the first usb drive you plugin, it will probably be /dev/sda1 if its the second, then /dev/sda2 etc etc
add this to the /etc/fstab to allow non root users to mount it... somthing like this...
/dev/sda1 /mnt/usbdrive auto noauto,user,sync,dirsync 0 0
the folder /mnt/usbdrive MUST exist, make it with mkdir /mnt/usbdrive
for more into, read "man mount"