Sidebar moves depending on browser’s window size.

I need help with keeping the sidebar in one place, regardless of the browser’s window size.

EX: If I re-size my browsers window, the side bar will fly to the bottom of the page if the browser is not wide enough for it. How do I fix this?

I’ve looked through all of the style sheets and other php files but can’t seem to find it. I understand how to fix this technically, using tables with an approximate width so that the main content and sidebar would stay where they were regardless of the window size, but I can’t figure out where the coding would be.

Thanks!!

-J