Associations
American Foundry Society - AFS - National

American Foundry Society - AFS - Birmingham

American Society for Quality - ASQ 

American Society for Quality - ASQ - Birmingham Section 1501

ASM - The Materials Information Society

The Copper Development Association

Educational Institutions
The University of Missouri - Rolla

Auburn University at Montgomery

General Interest
Classic Fiberglass boats - some oldies but goodies

Magazines
Foundry Magazine

Modern Casting Magazine

Quality Digest

Metallurgical
Metallography - lots of industry, information links.  Good discussion page on metallographic issues.

Quality

The cove  - a good forum and discussion site

Railroad related
Railway Technology - a listing of several railroad suppliers, railroad related organizations, conferences, etc.