A-Tech 32GB (4 x 8GB) PC3-8500 DDR3 1066/1067 MHz RAM for iMac Late 2009 27- inch (Quad-Core i5/i7) | 204-Pin SODIMM Max Memory Upgrade Kit at Amazon.com
iMac | 3.33 GHz Core 2 Duo | 27 Inch | Late 2009 - Techable.com
16GB 4x4GB RAM Memory for Apple iMac RAM Memory (21.5 and 27-inch, Late 2009) | eBay
How to Upgrade iMac Hard Drive (2009, 2010, 2011): EveryMac.com