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
Apple+iMac+24%22+Desktop+-+MA878LL%2FA+%28August%2C+2007%29 for sale online | eBay
Install memory in an iMac - Apple Support (HK)
iMac 24" 2.8GHz Core 2 Extreme (Mid 2007) | mac of all trades