I have a desktop iMac from 2007 and I have only the original software it came with. Also, when I scrolled to the Mac tab to do a software update it simply won't find lion in it. I suspect that I probably am just so far behind the new software that it won't let me make the jump.... SO what do I do to get the newest version?

the lion upgrade can be purchased via www.apple.com. once you download the program from the online apple store, follow the screen prompts.

the lion upgrade can be purchased via www.apple.com. once you download the program from the online apple store, follow the screen prompts.

Lion just makes your mac a big iPad, without a touch screen. Don't know why you'd want to, but here:

Go to Apple, and download the "App Store" application.
Open the application, and sign up with your iTunes store account.
Search for and download the OS.

apple menu - software update.