When you've got them sorted use some Meguires PlastRX
http://www.meguiars.co.uk/product/225/Plast-RX/
Or Meguires Headlight protector
http://www.meguiars.co.uk/product/45...ht-Protectant/
To keep them from going cloudy again.
I found the PlastRX can't be used with a machine polisher as it gets sticky when it gets warm due to the friction. There is a 3M kit available for restoring them as well which is supposed to be quite good.
Shane