Iray is a renderer, so it's settings being modified under "Render Settings" (screen caps posted earlier).

I be using outside source for IES profiles.  Each lighting maker supplies the profiles for their products (AFAIK, all free).  You can find easily on googles.

If you have dealing with other renderers for DS (i.e.,Luxus,Reality/LuxRender), you know that they have own materials.

The shader base and some examples for IRay are found under "Shader Presets"