Did you mean only in an ancestry tre when you said: "A Media file can only be linked to a Citation. NOT a Source. Check it out. Go to a Source. To get a Media file to that "source entry" you need a Citation."
A media file can be attached to a Source directly (and not though a citation) in FTM2012, but I don't recommend it, for the reasons I posted above:
http://boards.ancestry.com/topics.software.famtreemaker/7844...
I don't recommend it primarily because it becomes hidden - one can't see it in media "count" in the media column of the person page, can't see it as a media icon in the citation.
The media can be attached directly to a source in one of two places. In the Source Workplace, right click on a source and choose "edit source" then click on the Media tab.
Or, in the Person tab, one can choose to the Media tab at either add "new" source, or "edit" the source by the same Media Link.
kjnorway gave his reasons for attaching media directly to a source and not a citation at:
http://boards.ancestry.com/topics.software.famtreemaker/7844...
I personally think that the "hidden" aspect of attaching media to a source in FTM2012 overrides the positive reasons of attaching the "title page" directly to the source, but kj and I both have our reasons for doing what we do. I personally would add the link to a title page to each citation. Remember, it is only a link to the media that is repeated by attaching the title page of a book, for example, not the media for the title page itself.
As far as attaching media directly to a source in an ancestry tree, I don't have the slightest idea, as I don't do data entry in ancestry trees. All of my work is in FTM2012.