Some time ago, late at night, while channel-grazing at his home in the woods outside Vancouver, Douglas Coupland was felled by a thunderbolt epiphany. Suitably for a writer whose books poke and peer at a world intensely mediated and awash in consumer detritus, the epiphany played out live on cable-access television.

"It was this local business-advice programme, with this business-advice guy, and he said, OK folks, figure out what it is you don't do well, and then don't do it! And it sounds kind of dumb but for me it was 'WOW!' It seemed really powerful and it's really changed my life these past few years. And this came out on, like, Business Vancouver Today or something . . ."

Blearily slumped in an Edinburgh hotel lobby halfway through his latest book tour, Coupland explains how his fiction has lately opened out, its focus broadening to a wide-angle pan. He's gone out on a limb with his latest, All Families Are Psychotic, a barrelling, red-faced, pot-boiler of a novel.

"Someone whose opinion I value said, Doug, not enough things happen in your books, and maybe now I've gone too far in the other direction, with five things happening on every single page."

Here's the precis: a one-armed astronaut, Sarah Drummond, is preparing to board the space shuttle at Cape Canaveral and her family has gathered to wave her off. Her mother is dying of AIDS. A brother is dying of AIDS. Another brother, a seething depressive, is trying to persuade his girlfriend against an abortion. Her father is dying of liver cancer; his new girlfriend has been diagnosed with HIV. Things get complicated. Princess Diana comes into it. There's a kind of happy ending.

Coupland, a terrific noticer, has a prose style hyper-sensitive to the odd kinetics of contemporary America. He's great on junked motels and seedy bars and he has a way with skewed dialogue. All Families Are Psychotic amplifies the conventions of Springer Show dysfunction to fill new and ever more lurid shapes. It's a weird success.

"With these characters, it was kind of like being dragged behind a speedboat," he says. "But when your characters go off like that, it can be a sign of emotional intensity, so there's probably something there worth following."

The book's gestation was not entirely smooth and necessitated a change of publisher in the US.

"The book was essentially finished, just Windex and a cloth to go over it and it'd be done, and my then publishers in New York said, oh this is so uncommercial, we can't believe you wrote this, f**k off and die! Oh they really sprayed me with it. They said, how could you do this to us? And it really messed up my head, it was really damaging. The irony is the British have been saying, oh this is so commercial, don't you feel you're getting too commercial?"

He's been a victim, probably, of unimaginative expectation. Since emerging with the epoch-making and phrase-minting Generation X in 1992, Coupland has been perceived as a suave chronicler of zeitgeist cool and surface detail, but the projected image - sharp-suited ⁿber-geek mesmerised by modernity's strange lurches - has never quite chimed with the warmth and music at the heart of his books.

From the stories of Life After God, through to his bull's eye hit on Gatesian culture in Microserfs and the glorious millenial fable Girlfriend In A Coma, he's consistently attempted to dim the surface sheen and get to the crux of the matter. There is almost always in his books, towards the end, a moment of uplift. The turmoil stills, the chaos spins itself out and the narration emerges to clarity and honest-spoken truths. "You can make it if you try," is the essentially down-home message. Though an icon for the style mags, he's a curiously old-fashioned and kind writer.

He seems to have settled things with himself by now. At 39, he's esconsed back in his home town, with family and his old art college buddies close at hand.

"I couldn't be in New York any more," he says. "It's very jealous and very carnivorous and it doesn't matter what you're doing, you're always thinking 'am I being used?' Or else you're thinking, 'am I using them?' It's a very disturbing position to be in.

"Vancouver is very mouldable, it's not finished yet, it's still getting there. I'm comfortable there. It rains all the time, but it's this real friendly little mist, it's wonderful, it's identical to the rain in Ireland."

For somebody who supposedly heralded the age of the slacker, Coupland is incongruously busy and productive. He has frequent exhibitions of his sculpture and design, he maintains a vast website (www.coupland.com) with endless diaries and digital photography, he writes travel books and knocks out the occasional graphic novel in Japan.

"I don't feel prolific, I feel kind of lazy, I fall into these inertial troughs. Day-to-day I never feel like I'm getting much done, but over the course of a year I guess it adds up."

He's pretty set in his working habits. "I always write at night, between midnight and two. That's beyond standard, it's just mandatory. Generally, there are people who write late at night or else they write first thing in the morning. I really don't think that books get written in the afternoon."

In conversation, as he practically mainlines thick black coffee, he has a tendency to space off on peripherals. A double-decker bus splattered with Coors Light advertising chugs past outside and he recoils in terror. "My God! The ugliness!" The saccharine lobby muzak throws him too. "JESUS GOD!" he hollers. "WHAT ARE THEY THINKING!?!" He admits to some mild eccentricities.

"I can no longer eat food in restaurants. It's a really f-ked up psychological thing, started about two years ago. See in restaurants now they preheat your plate with a blow-torch and this nuclear cloud of heat arrives at the table and I go, ah, could you ask the chef to put this on a room temperature plate, which is not a hard thing to do, and then this big guy will come balling out of the kitchen going, hey, what's all this, and I go, look, the food's fine but I don't want it served on, like, a lava bed. Actually, my father hasn't gone to a restaurant in years and I always thought it was because he was cheap but maybe it's a genetic thing. Another thing is I'm not able to open letters, and that's pre-anthrax."

Something of a Europhile, Coupland is engaged by what he calls the tradition of "metropolitan fiction" here. He seems to consider himself a North American rather than a Canadian writer.

"In Canada the problem is that literature has been entirely to do with the immigrant experience, and small-town life, and, like, man-against-nature, and there are no exceptions. So that's made me feel a little alienated."

Like J.G. Ballard and Kurt Vonnegut, who are among the writers he most admires, his is often a fiction of the near future, but it's a near future very much informed by a kind of 1970s, TV-Kid sensibility.

"The 70s was when a lot of my critical associations were being made and I can't change that. But you couldn't get me to go back, you couldn't get me to go back in time 10 minutes. I remember it as the iciest, most stagnant part of the Cold War."

He's already mapping out his next novel ("I want to do something that's really deeply interior"), which he'll begin as soon as the reading tour is done.

"A thing I've learned about touring 10 years on is that it's too fractured for me to actually write as I go along. It's too fractured to plan out a trance, and when you're writing a book it's a trance, psychologically and I'm sure medically in some way."

In the meantime, Michael Stipe's film production company, which made Being John Malkovich, has snapped up All Families Are Psychotic and Coupland has a gaggle of art and literary endeavours simmering.

"All you really have in life is time and free will and I think wasting time is like . . . well, say there's a big beautiful buffet table with the most delicious food imaginable, and you tip it over. You can do anything you want in the world, to do nothing is like pouring chlorox over the buffet."