1) Can all elements be made into nano scale materials?
As far as I know, there are no stable elements which could not be made into something at a nanoscale. This is not to say it would be EASY to do - Fluorine, for instance, is going to be very difficult to handle due to its high reactivity, and some of the nobel gasses are also going to be quite difficult for the opposite reason, they're very inert.

2) Who and how are researchers developing nano materials?
You should realize that nanomaterials have been made and utilized for hundreds of years. Examples include various types of stained glass that are colored by nanoparticles of precious metals, among others. There's also the most common nanoscale manipulator we know of at the present time - biological life.
That being said, many major universities/colleges have varying degrees of research ongoing, as well as quite a few others in government and commerce. So far as I know, there is no one single source for listings of everyone working on some form of nano-scale science, at least short of Google.

3) Is there a governmental body trying to stay abreast of these products?
Yes and no. There's quite a few bodies, US and otherwise, who're looking at various pieces of the puzzle such as the US National Nanotechnology Initiative, but so far as I know there's no one overarching body within any nation. This is in part because nanoscale science covers so many different areas of scholarship it is rather hard to pidgeon-hole.

Hope this is helpful,
-John B