iMac 2.4 GHz (24-inch, Mid 2007) — Keane Mac Repair
Memory Upgrades for Apple iMac 2007 - Up to 6GB
Install memory in an iMac - Apple Support
Apple iMac 2007 A1224 MA877LL/A 20" C2D 2.4GHz 4GB RAM 320GB HD DVDRW El Capitan 885909150335 | eBay
6GB Memory for 2007-2008 MacBook Pro, MacBook, and iMac
iMAC 24" Mid 2007 Intel Core 2 Duo 2.8GHz 4GB Ram 500 HD Radeon 2600 (A1225) | eBay
iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
A-Tech for Apple 1GB DDR2 667MHz PC2-5300 200-pin SODIMM for MacBook, MacBook Pro, iMac, Mac Mini - (Early/Mid/Late 2006, Mid/Late 2007, Early 2008, Early 2009) - Memory RAM Module at Amazon.com