The Pixel Bible - Blackeye Software's Derek Yu tells you how its done.
So you want to be a Pixel Artist? - A series of specific game related tutorials. Lots of examples.
GENERAL PIXEL ART WEBSITES
Pixelation - A great forum visited by pixel artists of all skill levels.
Pixel-Zone Downloads - Some fun toys for pixel artists.
RECOMMENDED PIXEL ARTISTS
Mark's MMF Bunker - The layout may look familiar. This is my site :D
Chris Tessmer's Recent Sprites - Miscellaneous good stuff.
RhysD's Pixel House - RhysD's isometric lovin' site.
Final Redemption - Kon's site. Some serious muscle!
Chiashia Ly's Portfolio - Some beautiful Japanese-style sprites.
If you have any links you would like me to add here, please drop me a post on the Natomic Forums