Apple iMac Late 2009 All in One Pc i7 16gb Ram 2TB HHD 2.8gz Selling as Is | eBay
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
Install memory in an iMac - Apple Support
Apple iMac (27-inch, unibody, 2009) review: Apple iMac (27-inch, unibody, 2009) - CNET
iMac 21.5" Late 2009 (10,1) - CPU Upgrade E8600 | MacRumors Forums