Interesting, I am new to this and was not familiar with ^. The concern I have is that your search would not find:
<span class="calibre5">Now is the time for all <i>good men</i> to enjoy a coke.</span> or:
<span class="calibre5">Now is the time for all <em>good men</em> to enjoy a coke.</span>
This search would:
<span class="calibre5">(((?!<span).)*?)</span>
Code:
Unrelated, how do you get those "code boxes" to show up in your comment?
Ah, I figured it out.
In case I sound stupid, remember that I am just learning.