Here's a
large cityscape (visit for screenshot) posted on Google 3D Warehouse, whose
terms of service state:
Quote:By submitting, posting or displaying Content through the 3D Warehouse, you grant Google and its end users a worldwide, royalty-free, non-exclusive, perpetual license to exercise the rights in the Content, as stated below:
1. to reproduce the Content;
2. to create and reproduce derivative works of the Content;
3. to display publicly and distribute copies of the Content;
4. to display publicly and distribute copies of derivative works of the content.
It could make a great base for one or several city tracks. Sketchup can export to a number of formats so it shouldn't be hard to get it into a format that can be used to create VDrift tracks.