iMac (2007-2009) Memory Installation Video - YouTube
A-Tech for Apple 6GB Kit (1x2GB + 1x4GB) DDR2 667MHz PC2-5300 200-pin SODIMM for MacBook (Late 2007, Early 2008, Early 2009), MacBook Pro (Mid 2007, Early 2008), iMac (Mid 2007) - Memory RAM Upgrade at Amazon.com
CMS 4GB (2X2GB) DDR2 5300 667MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Apple® iMac (Mid 2007) Pc2-5300 - A37 at Amazon.com
iMac 20-inch (Mid-2007) Core 2 Duo 2.4GHz - HDD 320 GB - 2GB | Back Market
Install memory in an iMac - Apple Support
Apple A1225 24-inch iMac 7.1 Core 2 Duo 2.4GHz 320GB HD 2GB RAM Mid-2007 MA878LL | RecycledGoods.com
Install memory in an iMac - Apple Support
Memory Upgrades for Apple iMac 2007 - Up to 6GB
iMac 2.4 GHz (24-inch, Mid 2007) — Keane Mac Repair
A-Tech for Apple 4GB Kit 2X 2GB PC2-5300 667MHz Mac Mini iMac Late 2006 Late 2008 Mid 2007 A1208 MA589LL A1207 MA456LL A1200 MB138LL/A A1176 MB139LL/A Memory RAM at Amazon.com
Apple iMac 2007 A1224 MA877LL/A 20" C2D 2.4GHz 4GB RAM 320GB HD DVDRW El Capitan 885909150335 | eBay
iMac 20-inch (Mid-2007) Core 2 Duo 2.4GHz - HDD 250 GB - 4GB | Back Market
Apple iMac 20-inch 2007 2.0GHz Intel Core 2 Duo 4GB RAM 250GB MA876LL El Capitan for sale online | eBay
Apple iMac (4th Gen.) review: Apple iMac (4th Gen.) - CNET