Searching for this functionality (plugin?)

Hi

My client needs to find which AutoCAD plugin can supply the following
functionality in what she knows to be a quite simple ("3 clicks, ready
to print") process when the said plugin (or function, I don't know - I
just maintain her network) is installed.

1. It needs to overlay a user-defineable grid (say 15' x 15') following
the parameters of the floor plan.

2. Draw in circles or squares at the intersections within the grid to
represent installation sites of acoustical equipment on the ceiling.

Can anyone help?

Names, links, even proper vocabulary for Googling would be helpful.

Thanks,

Eric