The quad tree caused me no end of problems. First of all I was allocating the number of indexes I wanted in my index buffer instead of their size in bytes. Forgive me for thinking that DX would be able to do a simple num * sizeof(x) op without my help. That wasn't immediately obvious because the error only occoured when the app was shutdown.
I also had my most stupid mistake to date. I was wandering why I couldn't see anything on the screen, even though I was rendering without error. Finally I figured it out. My line of sight was on the same plane as my terrain making it invisiable. All I had to do was move my camera up and tada - there was my terrain.
On the plus side this is quite an acheivement for me to get the quad-tree working in one day. I am using a triangle fan to render each of the elements of the grid. THere is no real difference between it and a triangle strip in this instance so I went with the fan because they're cool (bow before the might of my punning)! I am only using unlit untextured verts atm, thats why I render in wireframe. Tomorrow I will add texture coords and the texture map for the terrain. Should have another screeny then.