Hi @timmym , I would suggest you to take a look at Blendswap to start with, there’s many free and non-licensed assets to use.
https://www.blendswap.com
Other website such as GrabCad.com or Free3d.com can also be usefull, though not as Blender-friendly (you will have to struggle with mesh conversion most of the time).
Good luck!
/Thibaut.
