Susan Furmage knows what she must look like standing there in Waterstone’s sobbing her heart out but, believe her, she is a normal person who holds down a job like everyone else. It’s just that she’s been waiting for this moment since she was 9 — shortly after John Lennon died and they played I Want To Hold Your Hand on the radio — and something inside her clicked. It’s been all about Paul ever since. That’s “Paul” as in Paul McCartney, but it’s funny how camping outside a bookstore overnight with legions of his other fans can give you this sense of entitlement: you can’t help but be on first-name terms.

The last time Paul did a signing in London the whole of Piccadilly came to a standstill because 3,000 people turned up. That was in 2000, with the release of a catalogue of his paintings. This year Waterstone’s has implemented the wristband policy favoured by organisers of open-air pop concerts. The first 200 people in the queue get a yellow wristband that guarantees them the chance to meet their hero. After that, out come 200 blue wristbands, which entitle their owners to a signed book and possibly some face-time, depending on how many autographs Paul can get through in 90 minutes. Hillary Clinton signed 500 copies of Living History in an hour, but you’d expect that from a former lawyer. Behind the people with blue wristbands is another queue of people without any wristbands at all and which curls down two flights of stairs and spills out on to the street. Their destiny is to return home empty-handed with the questionable boast that they spent the day in the same building as a former Beatle. In the end Paul signed 300 copies.

Wristbands have the added bonus of giving the fans something to take home with them, part of what booksellers now refer to as the bookshop “experience”. In the run-up to Christmas especially, book signings are a key part of that experience, having been transformed from earnest little queues hidden away at the back of a shop to stage-managed extravaganzas with undercover minders and “loss prevention officers”.

“Bookshops have remarketed themselves as lifestyle shops,” says Philip Jones, of the industry bible, The Bookseller. “They’re competing with other media such as DVDs and music and the huge discounts offered by online booksellers. Publishers are putting more emphasis on the cult of the author, especially celebrity authors, to attract a consumer audience.”

All of which translates as: Paul’s fans are not here to read. Jo Marino organises all the big events at Waterstone’s — Palin’s Himalaya, Pamela Anderson’s Star, David Beckham’s autobiography, My Side. Could Martin Amis pack a store like Pammy? “With someone like Amis we would do an ‘in conversation with’,” says Jo.

The strip of coloured plastic lacks the permanence that some fans crave. Michael Hobbs and Richard White, both from Portsmouth, became admirers of Paul after they discovered some of Michael’s father’s Wings records in the loft. Standing in line to meet their hero, they discussed their tactics: what they were going to say, whether they would get the chance to shake his hand and how many times they’d shake it if they did.

Wristbands can get lost or stolen, they reckoned, but not a signed limb. Would Paul say yes to signing their arms? It was a gamble, but in the end he agreed. “Now we’re straight into a taxi to have it tattooed on.”

Susan settles for the memories. She managed to say hi and tell him her name and that was enough for her. Susan’s not like this about any other famous people. Why Paul? “It’s something I can’t explain. There’s something about his music, the quality of his voice. He’s got this Paul McCartney face.”

Susan got married last year. “My husband did say to me that this moment was going to be more important than our wedding day. I tried to reassure him, not very convincingly.”

High in the Clouds — Paul’s book — is not a book for people of Susan’s age. It is written for children but there are conspicuously few under-10s in the line of 500 McCartney fans. Paul doesn’t get uptight about it, he says, that’s the celebrity game. “I don’t mind who buys the book at the signing, it kind of gets the word out.”

Even the fanatical fans he can relate to. “In my youth I was quite fanatical about Elvis Presley so I can certainly relate through my own worship days. I try to be excited for them. I wouldn’t want to remain austere and bewildered.”

Paul is an example of a person who gives good book signings. Ditto Bill Clinton — My Life (2003) — who spent his book tour contentedly swamped by admirers. Since then the number of people showing up to signings has soared. Last year 68,000 people turned up for signings at Waterstone’s alone, 14,000 more than in 2003. Often the police are roped in to help.

The bookshops like to keep signings comparatively discreet affairs: some more deliberately so than others — Trinny Woodall decided not to drag a Vogue photographer along to her personal appearance at Costco Wholesale in Watford last week. Of course, there is such a thing as too much discretion: the measly queue of 17 people who showed up to have their Eric Sykes books autographed last Thursday. Sykes was heard to exclaim: “Is that it!” Then a woman asked him if he wouldn’t mind autographing her plastic shopping bag. Certainly talent is no guarantee of crowds. The most reliable draws are famous sportsmen and the flawed stars of daytime television whose fans can be relied on to be free to make an impromptu pilgrimage during working hours. Thanks to them, Richard and Judy’s wine-tasting at Border’s Oxford Street last week was a smash hit , despite their no-show. Down the road a mob formed around the Selfridges window in which Gloria Hunniford publicised her new memoir — Next To You: Caron’s Courage Remembered By Her Mother — on live television.

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