Both me and Madame Contrex have dry skin, and when we lived in England we used Boots Sensitive Skin Laundry Liquid. £3.89 a litre online. We have it sent out here. There is also Ecover but it is more expensive and no better.
That's almost as bad as being told the local chemist is out of rat poison and being asked if I'd tried Boots, only to reply with, 'I wasn't planning on kicking them to death.'