They aren't really that high quality to be honest, most of them were obviously made from scratch in photoshop and it shows quite badly across a few. Even some of the textures that are tiles don't actually tile properly.
A lot of them aren't suposed to tile though. And of course they are designed for use in CGI applications not for games. If you have a look through the galler on http://www.3dtotal.com there is a section for total texture scenes and you can see how high quality they are when used by pros.
I'd quite like to get my hands on the two "textures from around the world" Cds, might buy one and take a look. I'll buy with my EMA just to piss you off 'thlete