Where to find index.php

Hi
I need to edit the index file in my blog.
Want to add a “Meta Tag” for a MSN Authentication. I search the site and found a stack of index.php and index.html – but none matches what I see in – View – Source – in the browser.

While I was looking for this, I noticed that my Blog doesn’t have a page title – where can I enter a title?

Cheers
admin (a) goldcoastwebwiz.com