It should probably come as no surprise that Marc Bolan does not want to hang out in the smoky VIP cabin of the Glastonbudget Festival – even if it does currently contain Anthony Kiedis and a surprisingly chummy Robbie Williams and Gary Barlow. If you’re the kind of bloke who famously drove a Rolls-Royce because, in some unfathomable way, it’s good for your voice, you’re going to want to look after your larynx in the lead-up to a gig. “Do you mind if we move? T-Rex fans are an obsessive bunch. If I’m slightly off with one of my ‘Ow!s’, I’ll be getting e-mails about it tomorrow.”

The theatrical throat-clutching, the eye shadow, the perfect ringlets, the dainty feet: it’s Bolan through and through. That said, I have been warned not to address the lead singer of T-Rextasy, the world’s premier T-Rex tribute band, as “Marc”. I am also not to call him by his real name, John Willans. I am to call him Danielz. This is the character he embodies: a tacit way of explaining to T-Rex fans that, while he might play the songs of Bolan, dress like him and, to some extent, live like him, he is not suggesting that he can replace the real thing. “I would not be doing this if Marc was still alive. There would be no point.”

Danielz sees T-Rextasy as “not a normal tribute band”, more a spiritual, wig-free journey into the Bolan legend. They are frequently joined on stage by original T-Rex members and, according to Danielz, when Bolan’s brother, Harry Feld, saw them play for the first time, he burst into tears. Danielz likes to distance himself from other tribute bands and said he hadn’t originally intended to play Glastonbudget, which is the UK’s biggest tribute-band festival. He relented when he found out that he would be able to play an “original acts stage”, to the side of the main one. He then took a dismayed look at the lineup (I have to confess that Subdüde and Icelandic Traffic Badgers mean nothing to me, either) and promptly asked to perform on the main stage.

T-Rextasy, who were formed in 1992, claim to be “one of the original tribute bands”. While that might seem like an oxymoron, and an exaggeration – the first tribute bands, both still going strong, are generally acknowledged to be the Rolling Clones (formed in 1979) and the Bootleg Beatles (1980) – they can at least claim to have been a frontrunner in a modern-day phenomenon. There is no official tribute-band directory, but it can be said that if you have been playing large-selling music in the public eye for three years or more, there will probably be a dozen or so people in the UK alone earning a living by pretending to be you.

Evidence of the tribute boom can be seen in the form of Glastonbudget itself. The festival – which takes place in Leicester-shire – made a £140,000 loss in its inaugural year, 2005, but can now sell 4,200 tickets on the wettest weekend of the year. In an era when a ticket to see the real Take That costs more than £60, and the cover version has been newly legitimised, it is easy to see the appeal of paying £47 to see Fake That when, into the bargain, you get three days’ free camping, and the chance to see Pink Fraud, Antarctic Monkeys and Oasish as well. Being in a covers band has never been more serious business. “We were really oversubscribed this year,” says Chris Dunn, one of Glastonbudget’s organisers. “And some of the bigger tribute bands are as hard to get hold of as proper rock stars.”

“We know that there are at least six or seven other Take That tribute bands out there, so we know we have to be on top of our game,” explains “Robbie Williams” of Fake That. They are an entirely different kind of covers group from T-Rextasy: a manufactured tribute to a manufactured band. As I speak to the pretend Robbie and Gary Barlow, their manager lurks in the background. Answering my questions about groupies (“We’re too busy for that!”), they glance nervously in his direction.

Fake That might have been a commercial enterprise, selected from auditions held after their management found out that Take That were planning to reform, but, had Take That’s Beautiful World album not been so successful, the bookings would not have come so thick and fast. To an extent, the fortunes of a tribute band will always mirror the fortunes of the people they are impersonating. The Likeness, a Cheshire-based tribute to the out-of-fashion pop-metal band the Darkness, played 41 gigs in 2004, 29 in 2005, but just eight in 2006, and have played only two this year (both in Macclesfield).

“We notice that we get more bookings when the Chilli Peppers are in the news,” says Fray Gordon, aka Anthony Kiedis, of the Ded Hot Chilli Peppers. Without his long black wig, Gordon doesn’t look much like Kiedis, but he has been mistaken for him. “It was a long time ago, but once, after a gig in Bournemouth, I pulled a girl who thought I was the real deal.”

Like a lot of men in tribute bands, Gordon is reluctant to reveal his day job and looks older than he is (he says he’s 30). Does he think that, with youth on their side, his group might be able to offer an energy that the proper Kiedis and co no longer can? “Neh, you can’t beat the real thing.” The tough talk is reserved for other tribute bands, such as another Chillis cover group that Gordon once fronted, but whose name he now refuses to speak aloud (“I’ll say only this: it’s the same as ours, apart from one letter”).

Most band rivalries in the tribute-group world make those between Keane and Razorlight or Girls Aloud and Lily Allen look like a game of footsy. Mention the Rolling Clones to the Counterfeit Stones, and be prepared for several minutes of hissing noises. Mini Kiss – a Kiss tribute, made up entirely of midgets – have long been publicly at war with Tiny Kiss, a splinter group formed by former Mini Kiss member “Mini Peter Criss”. Zeparella, an all-female Led Zeppelin tribute, might not be best friends with Lez Zeppelin, but the real rancour is between them and their old band-mates in AC/DShe. Can you be in a tribute band to one rock band, then form another tribute band to a different rock band, and still be “real”? AC/DShe think not.

“Being in a tribute band is hard work, and singing Robbie Williams when you want to be in the Who is as bad as commuting,” says Steve Elson, aka “Nick Dagger” from the Counterfeit Stones. It might seem preposterous that the eternal musical issue of “authenticity” is prized so much in tribute world, but it is probably no less preposterous than a Beach Boys containing only Mike Love. We live in an age when icons limp along the reunion trail into their dotage, when the notion of “originality” in music is more nebulous and patchwork than ever. Who is to say that, in this environment, the bands of Glastonbudget and beyond are not the future? One thing is certain: in their hollow, copyist’s way, they mean it, man – as much as anyone.

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