In case I forget this in the future, or if this helps someone else out.
I'm trying to setup evolution as an email client but I can't adjust all of it's font sizes.
The fonts within the emails themselves remains incredibly small after adjusting font properties in the KDE4 control panel and within evolution itself.
I used to use a gnome program to adjust font sizes for gnome applications in kde called gnome-font-properties, but it doesn't exist anymore. Now it's gnome-appearance-properties. This program typically appears in your /usr/bin folder. If you don't find that program, then install it with synaptic. it's a part of the package gnome-control-center.
More info:
http://live.gnome.org/Evolution/FAQ