INVESTINTEC.com A really good website for links to all the best training sites.
myCADsite Excellent FREE Autocad Tutorials at all levels
Affralisp One of the best Autolisp sites
CADTutor Excellent tutorial site
Jeffery Sanders Great Autolisp site.
JTB World Great Autolisp site.
ENGDS Examples of Lisp routines
CADforum List of Autocad commands
Attila G Horvath Good a description of the new Autocad Command line and other stuff.
Novedge Is Autocad still relevant
DesignSpark Mechanical A great free 3D modelling program
Lynda.com Layer Manager Tutorial One of the best Layer tutorials on the web
Center for the Study of Architecture (Archeology) If you really want yo see how complex Layer Names can become