SketchUp is a fast and simple 3D modeling program. You can use it to model simple objects, like your house. You can use textures and colors, too. After Google aquired SketchUp, they came out whit this free version. It is still not universal, but works well in Rosetta. You can export to 2D images or directly into Google Earth. Google also has a 3D Wharehouse where you can upload your models and download the other user's.