I have been looking around Magento now for a few weeks and trying to get to grips with the file structure. While I have learnt (on a basic level) where to put code I have created and learnt to understand some of the functions but I have not learnt how to locate a required file, which I need, when I dont have a tutorial saying where that required file is.
My question
What questions do I need to ask myself in order to track down the necessary file(s) to edit? for example, within in the admin area (product upload tab of the "new product" page) I need to add an additional function
What I've done
Turned on "template path hints" (doesn't seem to work on the admin area)
Looked at generated HTML to try and make a more educated guess as to where its located
Looked at URL to try and make a more educated guess as to location
Currently I'm looking in the App/Mage/Catalog/Product/Image.php. I believe this is one of the required files I need but I will also need several other files and I have been unable to find them