I think you have two issues here. The first is you want the same audio to be accessible and controllable from 2 or more areas, the second is you want to be able to listen to media from various sources (radio, CD, MP3, ipod etc). I would be tempted to speak to a specialist store; I think there is quite a market for this type of thing. It’s pretty common in commercial premises, pubs, shops etc

In simple terms you need an amplifier that feeds 2, 4 or 6 (or how ever many) speakers and something to play your source material (radio, cd, mp3, wma, USB reader) – some bits of equipment e.g. a laptop can play all your media, however, if you want to use separates (mp3 player, CD player, Radio etc) you will need to make sure your amp has the required number of inputs. – Did I say simple? grin