I've successfully used FTP to get to my site. How do I navigate to my website files?
On the server side (right window) you should see a list of folders. Look for the one that says public_html and double-click on it. Your index.php file is located there. Please do not change it. If you are over-riding NE1, you can upload an index.html file to this directory which will then show up instead of the index.php file. For graphics,  NE1 stores all of your uploaded files to web_images/ so now double-click on the "web_images" directory if you need to get to those files.