Wiring within new extension - sources of basic information please

[semiartificial]

I'm not sure I'm posting in the right forum - apologies if I'm in the wrong place.

Quick intro:
In about three months work will start on a kitchen/living room extension.
The surveyor wants to put out a fairly detailed spec of work for builders to quote against in the next couple of weeks.
It struck me that I need to be able to say what wiring is needed where
All I can say about that so far is there will be a TV in there, plus some sort of sound system (will need to buy, completely undefined at this stage, but it won't be full on home cinema!), plus games consoles (eg. PS3), plus laptop (we have wireless broadband, but can it connect to a TV? etc)
Yes, vague, sorry.

Why I'm posting:
I had a quick look at the 'read first' bit, and one of the projects included the statement "At this stage I made absolutely sure that all the cables I would need had been run to the stud frames at the correct locations - there will be no turning back now!"
Well, exactly, so I'm wondering if there are sources of info about this for uneducated people like myself!
The floor will be solid, including underfloor heating, so no opportunity to just 'run something under' later, and my wife would simply not accept any visible wiring running round the room (eg. oops, forgot all about an aerial cable for the TV etc), plus what about speakers (wireless??)
As you can tell I've given it very little thought.
But! ... I need to understand what (generic) cabling I'm likely to need and get it right first time, or I am dead meat.

Any help appreciated!

[hornydragon]

Check out the info here Video RF and Networks | Wired Life Basically you will need to decide what you want and where you want it and spec the cabling accordingly (and dont expect the builde ror electricians to know what cables you need, where to get them or how to install them. Instead why not contact a local specialist to discuss the options and guide you through what acheivable for your budget.