DBC Pierre could be mulling over the latest cattle prices or worrying about the silage. He rolls into Ballinamore in a 1996-reg jeep, lopes past a couple of chattering pensioners and into the Commercial Hotel for a cup of tea. He takes a seat, sips his tea and sparks up a fag. He looks like any local farmer taking a mid-afternoon break in this corner of what locals call “Lovely Leitrim”. Nobody pays him the slightest bit of attention.

That is just fine by Pierre — aka Peter Finlay, the winner of this year’s Man Booker prize, one of the most prestigious literary prizes in the world, who has chosen to live in one of the most remote parts of Ireland.

His past — an adulthood of drugs, thieving and betrayal (his friends nickname him Dirty But Clean, hence his nom de plume) — was rehashed in glorious detail when he was nominated for the Booker earlier this year. Vernon God Little, which has also been shortlisted for the Whitbread prize, announced in January, tells the story of a troubled and bored 15-year-old Texan schoolboy who is accused of helping a friend massacre their classmates.

So what on earth is he doing in Leitrim? Why not Notting Hill? Perhaps a pied-a-terre in Bloomsbury or a villa by the sea in Brighton? I mean, seriously, a house in the wilds of the midlands.

One explanation comes from the Irish actor Adrian Dunbar who said of this unfancied corner of Ireland: “The place is heaven. The reason it’s heaven is that it’s quiet and there’s basically nobody and nothing there. The question shouldn’t be, ‘What is it about Leitrim that people like?’, it should be, ‘What isn’t it about Leitrim?’ because there really is nothing there.”

“I had an Irish friend in London who gave us some help. I was looking for nice places to live and narrowed it down to half a dozen places in Cork, Kerry and then this place in Leitrim which was an outside shot,” says Finlay, who lives with Jennie, his Australian girlfriend of 12 years.

“But there was something about it. I had never been to Ireland before, but when I came here I fell in love with it. We paid ¤128,000 for this big abandoned house which still needs some work. We don’t even have a proper front door. I came here before all the Booker noise and people didn’t know me from Adam. We still got a warm welcome which is typically Irish but more so in this particular area. The hospitality was almost over the top. It knocked us flat.”

After emerging from the wreckage of his first 40 years, he says he is delighted to be writing but seems almost fearful of the publicity that has followed. Physically, Finlay certainly looks like life has given him a good kicking. His face is reddened from broken capillaries, the effects of alcohol and drugs. With his slightly unkempt appearance, he could easily pass as a vagrant.

This is the short version of what we know already of the first-time novelist; Pierre, a British citizen whose real name is Peter Finlay, was born in Australia, grew up in Mexico, was a drug addict, gambler and thief who was once jailed for bouncing cheques.

Perhaps his most spectacular act of betrayal was the sale of a friend’s flat in southern Spain while the owner, American artist Robert Lenton, was on holiday in America. Finlay was entrusted with overseeing the disposal of the property which was sold for €50,000. He legged it with the cash.

It gets worse. Chronically addicted to cocaine, heroin and pretty much anything he could get his hands on, Finlay racked up debts totalling €200,000 which he now says would have taken a lifetime of toil to pay off.

He enjoyed a privileged upbringing in a wealthy suburb of Mexico City where his Australian father Keith worked as a UN crop scientist. He died of a brain tumour when Finlay was just 19 and he admits that his father’s death sent him off the rails.

It was during his father’s prolonged illness that Finlay embraced drugs and gambling, embarking on an 11-year bender which took him to Australia and then London. His mother Patricia now lives in England while his sister Deidre lives in Australia.

So after two decades of hard and mostly dishonest living in which he endured dark depression and toyed with suicide, Finlay suddenly discovered discipline. He knocked the drugs on the head, locked himself in a south London flat and clattered out a book in five weeks flat.

He says: “Vernon popped up by himself in a strange way in 1999 when we didn’t have the dark shadow of terror, a new world order and shit hanging over us.

“Our culture, speaking of we white Celts and Anglos, was really engrossed in trivia and it seemed a mad farcical world that we were living in: completely ruled by money and fashion, and it just seemed we were becoming a quite ignorant culture.”

The inspiration came after seeing television images of a teenager being put in the back of a US police car after a high school shooting, his face blank and expressionless as the cameras zoomed in.

He says: “All of this was in my head on the day I saw pictures of this kid. It was before Columbine but came in the middle of all my musings of where our culture was headed. The pictures really touched me. He seemed in a way a motif, a twisted and quite sinister icon of the very dark edge of our culture. Because now, because of economic pressure on individual lives, you have to conform.

“And that makes you wonder about kids. What about those who don’t conform; the ugly one, the fat one, the slow one, the one who doesn’t quite fit into the mould. So that awkward image of the kid erupted in me and I started wondering what sort of life was around him. It grew into the book.”

Told through Vernon’s expletive riddled narrative, it was hailed by British critics. American reviews have almost entirely been negative, bristling with indignation over the satirising of US media and culture.

Professor John Carey, chairman of the Booker judges, hailed the novel as a coruscating black comedy “reflecting our alarm, but also our fascination with modern America.”

Finlay happily describes his first draft as a “pile of shit” which he spent another 18 months re-crafting before posting it to a dozen publishers. He says: “I put every ounce of blood and every last breath into this f****** thing. I mean it was my last gasp attempt. When you are 38 and your CV is a pile of crap, what’s the alternative? I mean I’d tried film making, illustrating and computers. I thought writing was the only tool I hadn’t tried yet.”

These days, Finlay has an easy almost Ballykissangel-like routine. Most days he pops into Ballinamore to pick up some meat from Scollens Victuallers and has a cuppa in the Commercial. Neighbours drop by with eggs from their chickens and fresh bread. On Saturday nights he heads for his local for a trad music session and few pints of Smithwicks.

A literary snob he is not. He says: “It’s amazing really. You’re in the pub and there’s the postman. In another corner is the butcher. Next to him the newsagent. I love the sense of community and belonging. It’s something I haven’t had for a while.”

He is at pains to point out that he actually lives three miles from Ballinamore in the parish of Aughnasheelin, something he says will give his local priest a laugh. Joan and Michael who run the post office-cum-shop near his house also get a mention. He says: “They are my publicity office. They get calls and check whether I want to speak to people and collect my letters. They’re amazing people.”

His girlfriend, whom he describes as “practical and down to earth”, is busy studying an Open University degree in international development after a decade as a merchant banker. He says: “She really helped me out when I was writing this book. Now I am helping her out by supporting her in this so she can one day work for the Red Cross or whatever.”

He met her in Australia after being introduced by a mutual friend. The pair then discovered they came from the same tiny street in the south Australia town of Reynella, near Adelaide.

He has come to terms with his life of excess. It was in the 1980s that he bumped into Lenton in the Spanish town of Almunecar. Finlay sold his friend’s home to pay for drugs and a scheme to find Montezuma’s lost gold. But he has finally made good the debt. Last month he sent Lenton a cheque for €100,000, more than double the original amount. Perhaps the ultimate blessing for his changed ways comes in an unexpected absolution from Lenton.

The friend he betrayed now says: “He lived a terrible life undercover and now he’s glad to be over it. Now he’s a good man.”

“We can start off perfect and get all twisted, all out of shape and go through some horrible periods and get out of them. If we are lucky. And he has been lucky.”