How to place 3D prefabs in a custom editor window

Hello,

I'm working on a tool to aid designers in level editing work.

I would like to have a custom editor with a sort of palette of common prefabs, used to create a level. I need this custom editor to show the objects as 3d icons (in a list where users can easily select them).

I didn't find any sample nor documentation about something like this. Is it possible?

Have you any documento or idea about how to achieve this task?

Thank you in advance!