You had said in one of my questions that a thin black granite strip would be good for a fireplace mantel shelf and the plasma can go 1 inch above it.
What materials do I need to do this? Would the granite be from a tiles store and just have them cut it to size? How much depth should it be? How far out and what do I need to secure the granite onto the drywall?
This is really not much more than a design 'vision' - black frame of the TV appearing to 'float' just above the thin black line of the mantel. If your question is 'where to get a piece of stone like that', my best guess would be a countertop fabricator. These guys can take custom orders to cut and polish a piece of stone to spec.
Attaching a stone strip can be done with either thinset mortar or stone construction adhesive. And NOT to drywall. I'd have a strip about 1-1/2" wide and 3/4" thick, rabbeted to accomodate drywall, and set into the 1/2" gap formed by tile backer, brick, and drywall.
It is impossible to consider the particulars without knowing what is there now and what is desired result.
Is entire wall painted brick? Is there just a vertical section of painted brick with drywall on either side? If so, is brick section proud, or flush with drywall? After tiling around fireplace, how is it to be finished on sides? Pilasters or something else? How will drywall above the tile 'tie in' with rest of the wall? Is it going to be flush with tile or not?
Oh, and just like other guys in the original thread, if you indeed "hired" someone, said hire appears to be rather inept - and it might be a very good idea to find an actual pro.