Some of these sites have good collections of links. Be sure to check them out.
LEGO The official Lego site.
LUGNET LEGO Users Group NETwork.  Site offers numerous newsgroups dealing with various areas of the Lego community.  Links can be found to other people's websites as well. The new memorial site for James Jessiman.  Links to various Lego-related software, including LEdit, MLCAD, and POV-Ray, can be found.
KEN-TUCKY LEGO CREATIONS A must see for Lego fans.
Karim's Legomania Provides lots of eye candy, especially at Pallas Spaceworks.
Neo Plastics Site has some good mecha designs in addition to a few other sci-fi models. 
Mladen's LEGO Creations Mladen Pejic's web site.  Good stuff.
Kingdom of Ikros Site has some very large dragons.
Mecha Hall of Fame Note worthy mecha builders.  Some are listed on this page.
Keppler Industries Space/Mecha i.e. scifi stuff
copyright 2000-2007, Travis C. Dickinson