A little Firebug help wanted-please

I have included a screenshot of my Firebug screen. My question is, when it tells me in the right hand screen what file to edit, how do I know where this file is? For instance, this shot shows that I should edit the stylesheet. But I have a few stylesheets. How do I know which one, especially when I do not know where they all are?

Just lay your mouse over the stylesheet.css on the right hand side and a fly out window will open and tell you the path...

O boy:dontgetit Here I go again.

See the included screenshot of my Firebug window. This was the result I obtained by "inspecting" the additional images in my listing at http://early1900photos.com/index.php?main_page=product_info&cPath=1&products_id=5

My goal was to find the file and the code that I would need to move to make the "aditional images" move to directly under the main image.

I took your advice and hovered my cursor over the "stylesheet.css" line on the right hand side of the firebug window. This DID show me the path to the stylesheet. However, the stylesheet info looks nothing like what is in the firebug window.

I also am including the stylesheet to compare to the firebug screenshot.

Normally you use the stylesheet.css to move div's and classes just a smidge or two...

To tackle this move you first have to do this:

https://www.zen-cart.com/tutorials/index.php?article=39

2. then control the rest in the stylesheet.css to align perfectly