This is going to be a reference page where I stick useful bits of data I find.

Druid Level 80 Hit, Expertise and Dodge
http://thebigbearbutt.com/2008/11/19/feral-druid-level-80-hit-expertise-...

http://www.warcrafthuntersunion.com/2008/12/hunter-stat-conversion-guide...
Ratings
32.78 Hit Rating = 1% Hit
45.91 Crit Rating = 1% Crit
32.79 Haste Rating = 1% Haste

Attack Power
14 AP (attack power) = 1 dps
Agility
1 Agility = 1 AP
83.33 Agility = 1% crit – or 1 Agil = .55 Crit Rating
79.19 Agility = 1% Dodge
1 Agility = 2 Armor

Armor Penetration
12.31 Armor Pen Rating = 1% armor reduction