I have tried to use SketchUp - mostly just learning by doing with occasional glimpses into the user guide. The program has a somewhat steep learning curve - and I may have been trying to use it for details it wasn't meant for. Anyway, I feel the tool was in the way, and for every hour I spent on creating my model I used 1-2 hours repairing things that had gone wrong; for instance, I constantly seem to be loosing "faces" on my walls.
I did manage to create a 3D-model of my house. The file is available here. Note how the roof is 3-level, with about 1 ft of separation between two levels.
