Ensure it is totally dry before you even attempt it. This could take a few days.Do not try to dry it artificially as this could damage the device beyond hope
If you tried this when it was wet then you could have toasted the circuitry inside as electrical current was provided to a wet circuit board. You should still try it when it is dry to be sure.
I have done this type of thing before and i find that if you let it dry completely then you could still get it to work long enough to get data off of it. But it's touchy, especially with the smaller cheaper hand held drives you can buy for next to nothing today.
if you really need the data then you can try accessing the device from machines with different operating systems. for example: If your drive will not be recognized anymore on your windows 7 machine then try it on a XP machine or a VISTA machine and the older drivers may be more fault tolerant than the newer drivers that ship with windows 7.
I feel for you though, water and tecchnology do not mix well
Just a tip: do not use the hand held usb drives for backup, these are flimsy in construction and are suited to transport files you do not wish to email. Use the bigger USB external hard drives for backup purposes.
Good luck my friend!