I've just discovered an entire google drive folder with over three hundred 3d models straight from the game, both d1 and d2, completely up to date.
The folder comes with a tutorial on how to get the models yourself in case there is a model you are looking for that is missing from the collective, and for all the others all you have to do is extract the .rar folder and shove one of the models into the program of your choosing ( such as blender, which is free, btw )
I cannot tell you how many things I've hesitated to draw just because I could not find a good reference. This person is doing god's work.
Happy Art-ing! ദ്ദി (•̀ᴗ•́ )