http://valk.dancing-mad.com/?page_id=179 has been amazing. Still trying to find a good forum for it, chocobro was but it seems to have slowed down.

crit seems to DR, so it isnt just "xx crit rate = 1%" as the xx changes
"Crit Chance % = 0.0693 x CRT – 18.486" is what he list

this is at level 50 btw