Directories (Materials, Supplies, Tools, Equipment)

Engineering Information (EI) Village
Engineering directories, Internet links, product catalogs & other resources

Grainger Industrial Supply
One of the best know names in tools and equipment.

McMaster-Carr Supply Company
Another great source of tools and supplies

Thomas Register of Manufacturers
This is the "grand daddy" of all sources of materials, supplies, and tools.   Over 155,000 companies providing all things needed to manufacture.  If prompted to log in, ID=cma  password=library