There's nothing like free software. And it's even better when it's a fully licensed version. What's the catch? Well, they're not the most recent versions. The free copy of SnagIt is 7.2.5 (current version is 8.2) and the free copy of Camtasia Studio is version 3 (current version is 5). But hey, it's free. And if you download and sign up for a free license key, TechSmith is offering upgrades to the latest versions at "special customer upgrade pricing discounts", which seems to translate to about half the price you'd pay off the shelf.
For SnagIt, download the demo version here (French and German versions are also available), then go to this page to request your free license key.
For Camtasia Studio, download the demo here (this one appears to be English only), then go here to get the license key.
UPDATE
It seems the blogging demons don't like FTP URLs, since they aren't being hyperlinked. Here are the plain text links for SnagIt:
For the English version: ftp://ftp.techsmith.com/pub/products/snagit/725/SnagIt.exe
For the German version: ftp://ftp.techsmith.com/pub/products/snagit/725/snagitde.exe
For the French version: ftp://ftp.techsmith.com/pub/products/snagit/725/snagitfr.exe