Where can I download pre-made themes for blender, and how can I put them to use?

Till now i only ran 2 instances of Blender and used the 2 existant themes to make sure i do things on the right project… But if one or two other themes (or a simplified sort of style sheet - ment for non-programmers - for basic colorations) would be disponible… why not…
you use these by either:
a) putting the downloaded script in your script directory (the default is blender.blender\scripts), opening a scripting window and clicking Scripts>Themes>The theme you want to use
b) opening the theme in blender’s text editor and pressing Alt P.
Control U to set the theme as default.

Thanks, I always wondered how to do it.

You know you can make your own too? In the user preferences? Save as many as you like.