Hey namesake!
Glen (one n) is a relatively rare name in my experience. Aside from predecessors in my family, I'd only ever run across one other throughout my childhood. Then, when working out west, there were 5 or 6 of us on one shift. It was nice not having to answer pages on the assumption it must have been one of the others!
I'm not going to tell you it's easy to use overall, but the suite of free (as both in "free beer" and "free speech" 'cause you can have the source code and modify/distribute as you see fit) image manipulation software from
http://imagemagick.org is nothing if not powerful. I only scratch the surface of its capabilities when I issue such commands as (should be one long line)
<font class="small">Code:</font><hr /><pre>convert -resize 30% -strip -sharpen 0x1 -quality 75 original.jpg modified.jpg</pre><hr />or
<font class="small">Code:</font><hr /><pre>convert -thumbnail 80x80 original.jpg modified.jpg</pre><hr />to first create Web-friendly images for attachments or secondly to create Web-friendly images for avatars.
In that (those) sense(s) it could not be easier to use, leaving the original ("original.jpg" in the examples) unmolested and providing a shiny new modified-as-directed copy ("modified.jpg" in the examples) alongside it.
There are several executables like "mogrify", "convert", "identify", and more, in the package. The one you'd be interested is "convert". I guess it's entirely possible to create web-graphics with fancy text entirely from the command line with the stuff. (see the tutor page for text at
http://www.cit.gu.edu.au/~anthony/graphics/imagick6/fonts/ [don't try to learn it all or even really understand it, just flip through the page and see the commands issued in the boxes and the results of the commands below them {the "\" at the end of a line of command merely means the command continues on the next line -- it's effectively all one long line of text}])
I used "composite" to wedge three different avatars (from people who'd said they couldn't upload new ones) into the one I've got for the time being.
Enjoy.
GlenS