Guitar Institute of Technology Publications
Berklee Shares
http://www.jodyfisher.com/products.html
Jody Fisher on Amazon
Howard Morgan's web site and publications (direct order)
Howard Morgan's publications on Amazon
http://www.alfred.com
http://homepage.ntlworld.com/s.castledine/greenfuz/wah.html
http://www.wah-wah.co.uk/
http://geofex.com/Article_Folders/wahpedl/wahped.htm