Timetec 16GB KIT(2x8GB) Compatible for Apple DDR3 1067MHz / 1066MHz PC3-8500 RAM for Mac Book (
Install memory in an iMac - Apple Support
A-Tech 16GB Kit (2x8GB) DDR3 1066MHz / 1067MHz PC3-8500 SODIMM RAM for Apple MacBook (13 inch, Mid 2010), MacBook Pro (13 inch, Mid 2010), iMac (27 inch, Late 2009), Mac Mini (Mid 2010) at Amazon.com
Apple iMac (27-inch, unibody, 2009) review: Apple iMac (27-inch, unibody, 2009) - CNET
Timetec 16GB KIT(4x4GB) Compatible for Apple DDR3 1067MHz / 1066MHz PC3-8500 CL7 Dual Rank for iMac (Late 2009 21.5-inch / 27-inch) SODIMM Memory MAC RAM Upgrade for iMac 10,1 and iMac 11,1 at Amazon.com
iMac 20-inch Early 2009 – Full Tech Specs, Release Date, and Price
2009 27" iMac Core i7 can take (2x8GB) 16GB DDR3 1600Mhz RAM? | MacRumors Forums
Memory Upgrades for Apple iMac 2009 - Up to 32GB
iMac | 2.26 GHz Core 2 Duo | 20 Inch | Mid 2009 - Techable.com