How to add widget ready sidebar

I just installed the Zip It theme and I love it BUT – I’d like to have a Widget ready left sidebar under the “about” page link on the left column. I just keep looking at alllllll that space down the left column…

Is there a quick, easy edit I can do to make that empty space into a left sidebar that I can put widgets into?

Or if I cannot do that – then where would I go to put code into that space?

Thanks for your help

Summer