Download Google Earth “Gray Buildings” models

Question

I need to work with the 3d model of some places. Google Earth has the 3d building layer with "Gray Buildings" in it. This would be exactly what I would require. Is there any way to get the 3d models that are used? Is there a Google Earth API (other than the Javascript stuff)? (I'm working in .net) that would help?

Or is there at least a manual solution how I can get these models, say, into Sketchup?

Thanks a lot!