Manufacturers' catalogs are excellent sources for detailed product information.

• EEM (Electronic Engineers Master Catalog). Detailed, technical information about electronic products.
• National Semiconductor Corp. Specifications for National Semiconductor products.
• Newark Electronics. Electronic components, tools, datacom, wire and more.
• Sweets Network. Guide to construction and building companies
• Texas Instruments Data Books. Technical information on Texas Instruments products.
• Thomas Register. Information to more than 152,000 U.S. companies and their products and services.