running wire in walls/floor

I am moving to a new house with hardwood floors and I would like it to have my wiring look nicer than what I had going in my current set-up. Who would I contact to run wires through the floor and or walls? I would like it done right and I know if I do it myself I won't be happy with the finished product. I have 2 rear surrounds and 2 rear centers that I will need to run wiring for. FYI: the walls and ceiling are plaster.