The main distribution site for is ftp.kde.org. However, this site is often under heavy load, so you might prefer one of the mirror sites. You can find an up-to-date list of mirrors here.
Yes, major distributions already ship . As building a distribution takes some time, they might not always contain the latest version, but for a start or to avoid downloading from the Internet, they do provide a good starting point.
You can find an up-to-date list of distributions that ship with here.
Currently, the latest stable version is 2.0.1.
The 2.0 Info Page contains a lot of information specific to this long-awaited release.
You can get the latest snapshots from ftp://ftp.kde.org/pub/kde/unstable/CVS/snapshots. You might also want to consider setting up your own CVS client in order to maintain the latest snapshot at all times. Please refer to How to use cvsup to get on doing that.
By the way, if you want to know what CVS is, please refer to What is CVS?.
is a C++-based class library to build user interfaces. It provides most of the widgets you will see in a application: menus, buttons, sliders, etc. is a cross-platform library that allows you to write code that will compile on systems as well as . You can learn more about at http://www.troll.no.