Custom Content Websites
From Platinum Arts Sandbox Free 3D Game Maker
- Before you attempt to make your own content for Sandbox, it's a good idea to look around and see if there's something else that is close enough to what you want. This saves you a lot of time and effort in trying to create good, high-quality working content. This is a list of some sites that may help you find what you want. In addition to this list, you can check out the list here to find even more resources. Please note that these sites may not be appropriate for children.
General Content (Includes multiple categories of content)
- http://www.turbosquid.com/Search/?max_price=0& (make sure what you want is free)
- First see here and here, other lists of free 3D content sites.