I myself (as recommended by Annie) was reading her book of the moment (see below) of "The Curious Incident of the Dog in the Night" last night - in bed, and noticed that typo which every good writer about the tube makes once in a while. Yup - on the map plan of the Bakerloo line (towards the back of the book, he says without trying to give too much of the story away) they'd written 'Edgware Road' as 'Edgeware Road' by mistake. Tsk! Very shoddy.
Edgware Road, or even Edgware is not a place that exists in the Meaning of Liff though. This is a classic book that did the rounds a good 10 to 15 years ago, (and was quite funny then, but I'm not so sure about now) and was a dictionary of definitions for things which previously didn't have a word.
My favourite? A "Huby" - "An erection large enough to be a publically embarassing bulge in the trousers, but not large enough to be of use to anybody". You get the idea.
Anyway, a lot of the defintions are named after place names in the UK, and whilst browsing through the index, I couldn't fail to spot 'Amersham', which is listed as:
Amersham - "Is the sneeze which tickles, but never comes. (Thought to derive from the Metropolitan line tube station of the same name, where the rails always rattle but the train never arrives)."