I've found the Ideal World customer services number!
It is 020 7649 7601 and this is answered with the same menu as the published premium 0843 168 0680 number.
See this press release Ideal Shopping Direct:
http://www.idealshoppingdirect.co.uk/PR20080603a.asp Quote:Eckoh Wins New 3 year Contract with IDS
3rd June 2008
Ideal Shopping Direct plc ("ISD"), one of the UK's largest digital retailers, today announced a new 3-year contract with Eckoh plc ("Eckoh"), the UK's largest provider of hosted speech recognition services, for the provision of advanced speech recognition and interactive voice response (IVR) solutions for product ordering and customer service.
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At the bottom it says "Eckoh provides automated services in virtually every industry sector for clients including TD Waterhouse, Vue Cinemas, William Hill, O2, Ideal Shopping Direct, DEFRA, The London Stock Exchange, the COI, National Rail Enquiries, AXA PPP healthcare, BSkyB, Parcelforce Worldwide, BAA, Barclays Stockbrokers, United Utilities and ScottishPower".