10 links
AdaPower.com
adapower.com
Extensive resource: developer resources, tools; FAQs, links, source code, people, references, books; COM/DCOM, CORBA; Linux, and Windows.
Cetus Links: Ada
cetus-links.org
Comprehensive listing of resources: Links, FAQs, Tutorials, Standards, ...
For Professionals
informatik.uni-rostock.de
It provides the Ada-version of the common flex and yacc for GNAT.