Hello,
The best way to do this is grab "Firebug" for firefox:
https://addons.mozilla.org/en-US/firefox/addon/firebug/You can hover over and "inspect" any HTML element on the page and see exactly what CSS is formatting it, this is going to be the best way to do this. As some files are template (for font sizes, colors) and some are VirtueMart CSS files
Regards,