I installed LMDE on my laptop the other day, after my brief foray with arch. I noticed the GTK3 apps looked terrible to say the least, so I tried to install my favorite gtk theme, zukitwo, which has the best matching GTK2/3 theme I've seen. I found that neither of the theme engines I needed were in the repos (murrine was way too outdated, unico engine not available.)
I managed to find a few debs on launchpad that install fine on LMDE and work perfectly with this theme:
http://packages.debian.org/unstable/x11 ... es-murrine
https://launchpad.net/~gnome3-team/+arc ... hive-extra
With these installed you can download the theme here: http://lassekongo83.deviantart.com/art/ ... -203936861 and just drop the them in your /usr/share/themes folder or your ~./themes folder.
Having these engines installed may also allow you to drop in ubuntu's ambiance gtk2/3 theme as well, but this unico package may be too old for that (haven't tried it). When I tried newer versions of the engines I ran into dependency issues with gtk3.
You will also want to edit your zukitwo gtkrc file and change nautilus-e.rc at the botton to nautilus.rc so nautilus looks normal, and change the gnome panel background to the one that comes with the theme. hopefully this helps someone
Screenshots of final result: