How to Upgrade iMac RAM (21.5" and 27" Aluminum): EveryMac.com
32.0GB OWC Memory Upgrade Kit For 2010-2011 Apple iMac
16GB -2x8GB Memory Ram Upgrade for 27" Apple iMac-11.3 Core i5 3.6GHz Mid 2010 | eBay
OWC a la Carte Upgrades for iMac, including eSATA, Memory, SSD option
Adamanta 16GB 4x4GB Apple Memory Upgrade for Mid 2010 iMac 21.5" and 27" DDR3 1333Mhz PC3-10600 SODIMM 2Rx8 CL9 1.5v RAM
iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
Timetec 16GB KIT(2x8GB) Compatible for Apple DDR3 1067MHz / 1066MHz PC3-8500 RAM for Mac Book (
iMac Upgrade Kits – iFixit Store
NEMIX RAM 32GB (4x8GB Upgrade) DDR3-1333 PC3-10600 204-Pin SODIMM Memory for Apple MacBook Pro Early/Late 2011, iMac Mid 2010 27 inch 4-Core, iMac Mid 2011 21.5/27” , Mac Mini Mid 2011 at Amazon.com
iMac RAM Models 11.3 (i5 and i7 only) to 12.2 (8GBx4) | MacMemory.com