My Book - 3tb - NOT Showing Up

The power interuption probably corrupted the drive. Try data recovery software like Recuva http://www.piriform.com/recuva is free and this one  http://download.cnet.com/EaseUS-Data-Recovery-Wizard-Free-Edition/3000-2248_4-75184619.html Maybe booting from a Linux Live CD will get you access to the data to copy it off.

Joe