I was digging through some old backups on Friday looking to see if I had any old versions of the Qt source code lying around. I didn't find those, but I found some gems I didn't know I had.
First, there's a presentation on the KDE internals I don't know where I gave, I suspect it was at MANLUG (the Manchester Linux User Group).
Next, there's a presentation The design of the K Desktop Environment.
rest here