Please use our Github-Project-Space, which you can find Here
Occasionally, we do offer consulting for Assimp related stuff. If you might need our help to integrate Assimp into your project, or if you want to sponsor Assimp development (i.e. add a particular feature), please get into touch with Kim and we'll see if we can do it.
CHAT VIA GITTER
And we also have an Gitter-channel at github. You can easily join us via: Gitter-Chat.