Education

High-Tech Productions.com
http://www.hightechscience.org/
Science & Technology Centers and Int'l Space Collection Located at Schools, Scout Camps & Museums Coast-to-Coast.

Materials and Supplies

Online Metals.com
http://www.onlinemetals.com/
Supplier of small quantities of a wide variety of metal stock in virtually any standard shape. Everything from stainless steel to bronze.

Thomas Register of American Manufacturers http://www.thomasregister.com/
A massive index of manufacturers and resellers who cater to industrial and engineering companies. A comprehensive index of items and materials with a list of suppliers for each entry.