Ward Cunningham's original FIT site: fit.c2.com
The Object Mentor FitNesse site: www.fitnesse.org
Gojko Adzic's FitNesse community wiki: www.fitnesse.info
Gojko Adzic's FitNesse resources: gojko.net/fitnesse
Paul Vlagsma's Fit Book examples: www.vlagsma.com/fitnesse
Cory Foy's tutorial: www.cornetdesign.com/2005/11/fitnesse-and-net-basic-tutorial.html
Brett Schuchert's FitNesse resources: http://schuchert.wikispaces.com/FitNesse