Magnus, Northampton (mail order also) tel. 01604 831 271. Www.magnusshoes.com.
Crispins, Chiltern St, London, tel. 020 7 486 8924.
Panache in Camberwell Road, Walworth Road, Camberwell, London SW5 (I don�t have any more info on this one, I am not even sure if these are two branches or a complicated address).
Sally Small tel 020 7 723 5321.
Small & Tall Shop, (also mail order), 71 York Street, London W1. Tel. 020 7723 5321
Nive to Elleven Footwear Ltd, (mail order), tel. 01420 561947, www.9211.co.uk
The British Footwear Manufacturers Federation once published a booklet entitled "Footwear for Special Needs". The address I had for them was 5, Portland Place, London W1N 3AA tel. 020 7 580 8687.
A journalist called Annalisa Barbieri who used to have a regular column on the Sunday Independent compiled "The Big Shoe Directory". If all else fails you could try tracking her down, I think she still writes regularly on various newspapers.
At the pricier end Jimmy Choo, Russell & Bromley, Hobbs and Jones Bootmaker do some styles in larger sizes, let me know if you want to know about these.
The end.