Partition Recovery From External USB Hard Drive

["Richard Brinson" <richard () kanoo-uk com>]

I am currently working with a customer who needs to recover data from an
external USB hard drive which has had it's only partition (NTFS) deleted.
Obviously Windows won't recognise the drive any more so I would like to know
if anyone has any neat tricks or tips to access the drive and rebuild the
partition without using commercial software, and preferrably via USB so I
don't have to rip the drive out of it's casing.
 
Many thanks
 
Richard