Open a terminal window and issue:
hdparm -I /dev/x
where x is your drive. If you're not sure of your drive label, use something like GParted (included in most Ubuntu releases afaik) to determine it.
This will print out a substantial amount of information about the device and you should see a line detailing the firmware revision.
just to make sure: that is a -I (as in captial of "i" correct?) Or is it a lowercase "L"
Correct, uppercase "i"