I am tied to Subscribe2 wordpress plugin, I wish to place an application for instance in footer section of my blog, but plugin's documentation only discusses putting a form inside a "page" while using "[subscribe2]" shortcode.

How do i place a subscribe form within the footer or tab area?

Normally you utilize shortcodes within the WordPress editor, but when you need to play one directly inside your theme files (say, footer.php), make use of the do_shortcode function:

echo do_shortcode('[subscribe2]');