Here are a few links that you might find interesting.

Hess Machinery Head Office
http://www.hess-maschinenfabrik.de

The National Concrete Masonary Association
http://www.ncma.org

World of Concrete
http://www.worldofconcrete.com

1g

Masonry Expo 2001
http://www.masonryexpo.com

The Interlocking Concrete Pavement Institute
http://www.icpi.org