Is it possible to download OSX updates I'm helping a friend update her iMac's OSX from 10.6.8 to the latest available for the hardware. That would be easy, if it weren't that the computer has only a 56k connection to the Internet, and so downloading updates would be unfeasible (and ridiculously costly). I don't have access to any other machine running OSX, only Windows and Linux. Also, I only have an unlimited internet connection at work, so physically bringing the computer there is not an option.

The computer is an iMac10,1, Intel Core 2 Duo @ 3,06 GHz, 4 GB RAM.

What are my options?
Fortunately the iMac can run Yosemite, the latest version of OS X. The only option you have is that find someone with a App Store account and ask him/her to get the OS for you as it's free to download for Mac users. Then make it bootable.