Forgot to mention this in my review. I ordered the map of various London shopping districts from the Streetsensation site (www.streetsensation.co.uk) before I left home. The unique thing about this is its a series of maps on regular sized paper in a clear cover with a slide off binding. You can remove just one page if that is all you want and easily take it with you. The front page says you are free to make copies and share it with friends. It shows you what stores are where all along the streets, where the cross streets are, locations of banks, pubs, etc.
It has a page that shows a photo of the street at the tube exit for that shopping area, tells you where to walk for what, etc. For each map page, a list of shops, pubs, etc., are grouped by category and listed on the back, with their symbols. You can tell, standing in Clarks on Oxford Street, how close you are to the nearest ATM, for example.
This helped tremendously the day I was on a solo errand to quickly find Soccer Scene on Oxford Street. I consulted the booklet, looked for the sports shops on Oxford Street, the hotel called the short list of stores until they found the items I needed at this store, and had them waiting for me at the register when I arrived. I could have been hopelessly turned around and lost a lot of time wandering when exiting Oxford Circus tube station without the map.
Not a substitute for your A-Z, mind you, but a nice enhancement if you plan to hit the shopping areas and want to plan your route. Also has a page showing locations of the markets, what they offer, days open, nearest tube, etc.
I don't recall what I paid for this, but it was not too expensive and very well worth it.
Hope it helps someone here!