Introductory books:
http://www.ati-net.com/atibooks.php

You can order all books about Alexander Technique through following link:
http://at-ffm.de/service/4_sprachen.htm
http://at-ffm.de/service/uebersicht.htm

http://www.alexandertechnique.com/bookshop/

http://www.stat.org.uk/pages/publications.htm

Alexander Technique Bibliography Database
Alexander Technique bibliography database website
www.mouritz.co.uk/5.00.Bibliography.html