In the link that calls the page you can see the name of the page. Start with the start page (index.html or something like that) and work down till you found the page you want to edit.
But you can't edit directly from the browser. You need to edit the file in your local copy and then ftp the changed file.
I've had a website built through joomla. I'm very familiar with Joomla but now want to start editing code in the files for layout, graphics, functions etc. things that aren't in the joomla extension options.
The fastest way for me to learn would be a way to know how to locate which files the source code is located in, follow the path, look up the code in a book to understand it and change to my desired outcome.
I just need a step by step guide on how to do this? or someone to show me over skype who I can pay per minute?