Here are 4 free 3D Models I found that might help you out:
1. A very detailed 3D moon model. http://bit.ly/jrOkAq
2. Free C4D earth model that is very high res. http://bit.ly/ebvBdT
3. Free swivel chair curtesy of Michael Ciesielski. http://bit.ly/mzEgA3
4. Free C4D satellite which is modeled extremely well and includes great textures. http://bit.ly/iE5p8R
If you know of any great free resources I can share, please let me know!