It is very likely that the drive is dead now. Sorry, but hard drives are very very susceptible to shocks like that. Especially if the drive was running when dropped. If you can RMA it, I would try, but you might just be out of luck on that one.
if the drive is still showing up the you should not waste anytime and run any free recovery utility and copy all the data off. do keep a close watch if the data transfer seems to be slowing down or you notice any strange sound coming from it. Keep us informed
If everything else fails, before you throw it away - put it in a zip-lock bag, and put it in the freezer for couple of hours. Seriosly..
I know this thread is old but i have to say i heard this when i was a kid about recovering data off busted HDD and never believed it. Today i was at wits end and last ditch effort threw the drive in the freezer for 4hours.
Sure enough it started up perfectly and only started skipping 3hours later.
i can still access the data its just super slow and dont want to risk unplugging untill everything is copied across.
So bottomline, people if u have no other option, i say go for it, just wipe the condensation off the drive (esp the terminals) before reconnecting!! and you should be good to go for at lkeast a bit of data recovery. Obviously all depending on how seriously damaged your drive is. Mine only fell a meter or so to the floor in its casing.