Hi ppl. Need some help here.

I've recently bought a house which comes with an existing home theatre system i.e. hanging wall speakers, s-video cable, etc. for projectors. However, I plan to change the system to a more updated one, mainly for viewing HD on the projector. It requires hacking i believe..(previous wires all embedded into the wall...)

Can someone point me to someone whois reliable and is able to give me advice on the type of audio and video system i should upgrade to?
Contact no perhaps?

Tks.