SME
http://www.sme.org
Society of Manufacturing Engineers
SME is a good resource for all professionals. This site is also the home of Manufacturing Engineering Magazine, Forming & Fabrication Magazine and Automotive Plastics Magazine.
ASTM
http://www.astm.org
American Society for Testing Materials
This site is the resource for standards.
Industry Magazines
Modern Machine Shop
http://www.mmsonline.com
This site is full of interesting articles and links related to the machining industry.
Tooling & Production
http://www.manufacturingcenter.com
This site is a good resource for the machining industry professional.
Cutting Tool Engineering
http://www.ctemag.com
An excellent resource for improving your manufacturing process. Cutting tool improvement and optimization is always a topic.
Injection Molding Magazine
http://www.immnet.com
This site is an excellent resource for the molder looking for industry news, technical articles, and the latest products.
Plastics Technology
http://www.ptonline.com
This site is a good resource for the plastic's processor.
Forging Magazine
http://www.forgingmagazine.com
This magazine is dedicated to improving the forging process and providing technical resources to the forging industry.