Seems like a dumb question, but I am wanting to add text to the top of an album page once the thumbnail is clicked on.

In other words, the text is not to appear alongside an image, but at the top of an album after that particular album has been selected by the user.

Using zenphoto 1.4.4.3 with galleriffic theme.

So you want the text only if the user has viewed the image? You would need to store somewhere the users who have viewed the image and check that list when the album script loads. If the user has viewed the page you set the style attributes of the text element to diaplay:block if not you set it to display:none.