Xbox Help, lost my data

I connected WD my book  to my X-box 360 and lost my Data, does anyone know how to retrive it ? If it’s possible?

Are you unable to see the drive, or its file system?

Can you hear the drive spin up?

Can you see it in Disk Management? Device Manager?

Can you see the USB enclosure with Microsoft’s UVCView utility?
http://www.users.on.net/~fzabkar/USB_IDs/UVCView.x86.exe

If the drive is OK, I would use Microsoft’s Sector Inspector utility to capture the “MBR, Partition Table(s) and Volume Boot Records for every disk connected to your computer”:
http://www.users.on.net/~fzabkar/SecInspect.zip

Extract the above archive to the one folder and execute the SIrun.bat file. The procedure will generate a report file named SIout.txt which you can then upload to a file sharing service so that we can examine it.