Web links
The following links may be useful.

  Site for downloading building instructions.

  Another site for downloading building instructions.

MLcad program (Cad/Cam) for designing lego models in 3D.

 3D viewer to view and rotate lego models in 3D.

 Sub-directory of Parts Tracker which is very useful.

Program to make and compare inventories of MLcad files.

Overview of all official released building instructions.

Website for discussion groups, web pages and services

BrickShelf site showing photo gallery of peoples own models.

 Construction site: Very impressive site about technic models!