Check out lots of cool Camtasia resources from my buddy Peter Gillberg: http://screencastprofits.com/callouts
This is a trick I did a few years ago in Camtasia 8. I've updated it for Camtasia 9 & higher.
By duplicating a text callout a bunch of times and manipulating the Z position parameter, you can "extrude" to text into a 3D looking text object!
Useful technique for Title clips, text logos, or anything you want to add a 3D touch to.