LLS is a great (set of) books, but more as a reference. Not so much as a teaching manual.
The best teaching book in the lockpickfield to my opinion is http://www.tresoroeffnung.de/buch.php
by Oliver Diederichsen. A visual guide to impressioning (and as he is the winner of last weeks german competition he knows his stuff)
The site is in German, so is the original book; make sure to order the english version.