Walking Jane Austen's London, A Tour Guide for The Modern Traveller, by Louise Allen, is a beautifully illustrated gem of a book. Even if you will never physically tread in Jane Austen's footsteps it is well worth reading.
"This book presents nine walks through both the London Jane Austen knew and the London of her novels. Follow in Jane Austen's footsteps to the Prince Regent's vanished palace, see where she stayed when she was correcting the proofs of Sense and Sensibility, accompany her on shopping expeditions. ...etc."