Sandi Thom is the Scottish lass who rocketed from obscurity to pop stardom after her song I Wish I Was a Punk Rocker (With Flowers in my Hair), was spontaneously discovered on the net by fans disgusted by the record industry’s hype of more bloated artists. Either that or tiny, innocent-looking, freckly, chatty Sandi Thom is a product of that industry’s most cynical and devious marketing strategy yet.

By the time I meet her there has been so much press, pro and anti, I don’t know what to think, although my suspicions are stoked when I am invited not to the South London flat from where what even she calls her “infamous” webcam concerts were broadcast but the swish West London offices of her record company. This is the very outfit that has sent newspapers a heavy legal letter warning that allegations of an “internet scam” were not only false but will “most likely have a significant and long-lasting detrimental effect on a promising new British artiste, at a very critical point in her nascent musical career”.

What, I wonder, if this “piss-stained basement in Tooting” (the description is her manager Ian Brown’s) is itself more virtual than real? But then Thom begins describing the scene in it this morning. I promise you, you could not make up a basement like this.

“Ian, my manager, came in to take me here and I’m in the same bed as my tour manager, Lizzie, who’s also my best friend.” Sharing a bed? “Yeah, that’s fine. It’s all fine. It’s not for any other reason but the fact there isn’t that many rooms. But Ian walks into the kitchen this morning and turns the kettle on and has to get past Craig (Connet, her drummer), who’s lying on a mattress on the kitchen floor.”

Er, just how squalid is this place? “Ian’s said that about the stains because he saw it when I first moved in but since then I’ve actually painted and made it nice. It’s all lovely now, even though it was on a very modest budget, spray-painting radiators gold and stuff.

“When I moved in, it was quite dowdy. Downstairs was just kind of full of bits of furniture and random things. It was a dark basement and I found a dead mouse in there once. But we painted the walls white and now when you walk in it’s just covered with signatures of people who have been here. It’s such a cool thing because it’s like a piece of history and it’s really nostalgic for me. I just sit there and look at it and go, ‘Wow, this is almost like rock’n’roll history’.”

But no blue plaque on the wall yet awhile? “Noo,” she laughs Scottishly. Has the rent gone up? “No, the rent’s not gone up at all. My landlord’s very good.”

Even though he must have read she’s been signed by Sony BMG for £1 million. Has she seen the colour of their money yet? “I think you’ve got to sell some records, do that first, which we are doing.”

But is it £1 million? “I think that it’s kind of the common practice to say that it’s a million pounds. Jamie Cullum signed for a million pounds; I signed for a million pounds; so and so did. It’s just what people say.”

Thom, I am finding, is an odd mixture of streetsmart and romantic, although the survival of the latter quality is the odder thing. Although she is still only 24, she has been in pop groups of one sort or another for ten years, gone to music college, had informal advice from Sir Paul McCartney, one of its visiting lecturers, and done session work for commercials and other bands. If she’s not cynical about the music business by now — and she does not appear to be — she is never going to be.

The debate over whether the success of her “virtual world tour”, Twenty One Nights from Tooting, was homemade or manufactured will, I suspect, look pretty arcane a few months from now. She has a beautiful folk-rock voice and writes both her own (often catchy) tunes and (sometime funny) lyrics.

Her songs appeal widely. Rolf Harris is a fan. So is the veteran Radio 2 DJ Johnnie Walker, who first played her last summer. But so are pre-teenage girls who, attracted, she surmises, by its nursery rhythmic quality, have been buying Punk Rocker at Woolworths on Saturdays in droves.

For the record, the audience for her virtual concerts started at 643 on February 24, which for someone who once played a gig in Glasgow to an audience of ten, was impressive enough. By March 4, 86,325 were watching, but this figure was not achieved simply by word of mouth. Thom’s management had fired off a million e-mails advertising it and persuaded a streaming company, Creative Tank, to lend the necessary bandwidth for thousands to view it.

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