The BBC used to use realplayer, now they are using a lot of flash. I have Adobe's Flashplayer 9 for linux installed, and the BBC is excellent.
Please note that if you live outside the UK, the BBC site may not work at all for you (because you haven't paid for it).
Can anyone tell me if I can get the sound from items on the BBC website and if so what do I have to do
If we have misunderstood your Q, and the BBC is working for you, and you want to record audio, I don't think you can. When they used .rm streams, you could
capture the audio to disk with mplayer,
but I don't think that works any more.