I know a good carpet cleaner - they have been coming to clean my white and cream carpets (laid pre-children!!) for years. They have recently been distributing leaflets locally with 1/2 price discount:
Wizard cleaning
http://www.wizardcleaning.co.uk" onclick="window.open(this.href);return false;
All the cleaners are good but I request MARK. The guy who runs the company is Jon who is also good.
Telephone number: 0208 653 4157.
They also do sofas, curtains and mattresses and one-off spring cleaning of the whole house.
The minimum charge is £22 and remember to ask for the discount!