Upgrade to Lion 10.7
I have an early 2007 iMac6.1, 2.16 GHz Intel Core 2 Duo, 2GB 667 MHz DDR2 SDRAM recently fitted with a 500 GB hard drive. I am running OS X Snow Leopard 10.6.8 but want to upgrade the OS to be able to use iCloud. This iMac is not compatible with Mountain Lion or Mavericks so Lion is my only option but I cannot find it in the App Store. Any suggestions?