3DGS has a lot of model resources and sites with contributions from a lot of other people! Search some of the links on the "Links" page and I'm sure you can find all this out real easily. The community here is very large and active, and contributions are made on a daily basis! If you can't ever find what your looking for don't hesitate to make a User Request and see if anyone is up to helping you out on your search, or by making you one!

There is a program you can download on the Download page (down a little bit) that does just what your asking for about 3DS importing. It imports 3DS Models, Textures, and Animations directly into 3DGS use. So if you can find a 3DS model from other large communities, it's easy to bring into this engine!