How to customize site to have two sidebars?

How to customize site to have two sidebars?

Well I am currently satisfied with a theme that I'm using, its very elegant and simple. The only catch is I want to have two sidebars ! Is there anyway to alter the code and have two side bars. It would be really great if am able to use the right space that is not utilized. It would let the visits not to scroll much to the bottom.