in reply to trying to find <head> in a string
Some advice not-so-directly related to your problem.
If you're parsing HTML, and think (even the slightest bit) that you'll need to update your script to accommodate other tags, might I suggest HTML::TokeParser. TokeParser's a module that's good to know, and is great for making changes to strings of HTML.
For projects larger than a one-tag only parser, use TokeParser. Learning it will sharpen your skills in HTML parsing, array and hash refs, and OO module use (if you aren't familiar with them now).
John J Reiser