I have just installed Archlinux & openbox but i have to say i am a bit dissapointed that the applications have this dull greyish (win 95) look:

On the picture there are two programs open which are gedit and gcalc which they both use GTK themes. I fixed those to look better by installing lxappearance and setting Adwaita theme. The calculator now looks way better while gedit doesn't:

I mean they both use GTK themes. Why don't both look better?
Then there is another side to this topic. I am using Kile and this one uses QT theme. How can i make it look like a real QT application - like the ones on KDE desktop? If this is impossible how can i at least make it look like a GTK app?
It looks dull atm:

EDIT 1 After applying the solution my Archlinux with openbox desktop manager looks like this:

EDIT 2 The only problem I've had with the look of applications from this point on was with the propietary software like VLC and Eagle. Look of the first one can be corrected by opening VLC and in /tools/perefferences/interface choosing GTK+. I haven't found the solution for the later one yet...