It’s getting harder and harder to resist the call of the blogs. I don’t mean that I can’t stop reading them. It’s that as I click around sites about gossip and gadgets, pickles and politics, I can’t help wondering whether to start one of my own. After all, if so many others can find fame and fortune from their corner of the internet, isn’t it worth a try?

Henry Copeland, founder of Blogads, which connects bloggers and advertisers, understands the temptation. “It’s the Horatio Alger story of the 21st century,” he says.

Copeland points to the wild success of “Perez Hilton”, a sassy online gossip columnist who started his blog just two years ago and now registers 100 million impressions a month. With his sniping comments such as “Need Stylist” scrawled on celebrity photographs, Perez has a cult following – and a brisk advertising business to show for it.

“People look at that and say, ‘That could be me too’,” Copeland says.

Jim Furtado is one of those hoping for cyber success of his own. Furtado started his blog, Baseball Think Factory, nearly six years ago when he was working as a fireman in Massachusetts and had lots of free time. “Every firefighter has two jobs,” he explains. But what began as a hobby has slowly become more like a business, and now the Boston Red Sox fan says he spends about 40 hours a week working on the site – in addition to his regular job. Furtado is a bit frustrated, his time for writing about baseball crowded out by the demands of keeping the technology working and chasing down ads. “It’s not as much fun as when I first started it,” he says.

The site has well over a million visits a month and brings in a little more than $1,000 a month from ads, but Furtado is trying hard to boost that. “As you start spending tremendous amounts of time, your wife says, ‘You better start making money on this’. ” But he knows it won’t be easy. “I’m going to have to put in even more time.”

Furtado is far from alone in spending long hours on his blog. The word (shortened from web log) was not used until 1999, but today there are 57 million blogs around the world, with new ones being launched at a rate of about 100,000 a day, according to Technorati, a blog tracking firm.

A poll last year by the Pew Internet & American Life Project found that most US bloggers do what they do to express themselves creatively and to document, and share, their personal experiences. Only 7 per cent said their main reason for blogging was to make money.

But the market for blog advertising, while just a fraction of total ad spending, has quickly become surprisingly large, hitting an estimated $36 million (£17.9 million) last year, according to PQ Media, a Connecticut consultancy. With its promise of engaged readers in key demographics and market niches, spending on blog advertising is expected to continue its rapid growth and top $300 million by 2010, the group says.

Blogs can bring other kinds of success, too. Julie Powell, who called herself a “government drone by day, renegade foodie by night”, became a blogging superstar in 2004 when she chronicled her attempt to cook all the recipes in Julia Child’s Mastering the Art of French Cooking in a single year. The buzz was so great that she got a book deal, and the resulting Julie and Julia: 365 Days, 524 Recipes, 1 Tiny Apartment Kitchen was a bestseller.

Clotilde Dusoulier, a Parisian woman (who writes in English), is hoping that her food blog will prove a similar launch pad. “The blog was created in September 2003, as an outlet for someone who feared her friends might tire of having their ears bent about what she had cooked/eaten/baked/bought, although they didn’t seem to have a problem with being fed dinner,” she explains on her site, Chocolate and Zucchini.

“One thing led to another, a bit of media attention was received, articles were submitted to and published by newspapers and magazines, a book deal was signed, a day job was quit, and a new life as a full-time food writer began.” Her book, Chocolate and Zucchini: Daily Adventures in a Parisian Kitchen, was published in the UK last month.

So why do some blogs bring in the big bucks and others founder?

Successful bloggers must work long hours – “18 hours a day, truly compulsively”, Copeland says. They also need the guts to commit themselves fully to their projects, even if it means uprooting their lives. Perhaps most importantly, they need to cultivate a voice that will attract readers and keep them coming back. “Voice is a one-in-100,000 kind of thing,” he says.

Copeland’s five-year-old business, with ten employees in North Carolina who sell ads on blogs and a dozen more in Budapest who work on programming and customer support, is one of several that have sprung up in recent years, connecting blogs with advertisers and allowing bloggers to run ads without dealing directly with advertisers.

The rates vary wildly – about $10,000 a week for a prominent spot on a big-name site, and $20 a week for an ad along the side of Half Changed World, “musings on work, parenthood, gender, politics, and the rest of life” by a self-described Washington “mom/policy wonk”. All in all, Copeland says, there are hundreds of people who get monthly cheques of $100-$1,000 – and a much smaller group for whom “it’s a real business”.

Darren Rowse has managed to make blogging a business. Based in Melbourne, Australia, Rowse started blogging when he was the minister of a church. Now he still ministers, but as a volunteer, instead drawing his income from his blogs, including Pro Blogger, and from related activities such as consulting, speaking and running a blog network. In an e-mail, he said one common mistake that he sees bloggers make is to get obsessed with one particular element of their blog at the expense of others. “A successful blog needs a number of things going for it at once, including good content, usable design, a marketing strategy to find readers, search engine optimisation” and other things.

That said, it’s clear to Rowse that the blogosphere rewards the quirky. A case in point: Manolo’s Shoe Blog, which mixes footwear advice, criticism, and celebrity sightings. The blog’s anonymous author, who writes in the third person, told Rowse he earns “in excess of six figures a year”.

Rowse cautions that it is hard to turn a blog into a thriving business, “but with a long-term vision, sustained hard work, a lot of creativity and some luck it’s possible . . . I mean, I was a guy whose computer expertise extended to knowing how to send e-mail and use a word-processor four to five years ago and now I make a living blogging. If I can do it, I suspect that others can.”

With all that encouragement, I asked Copeland if he had heard any dramatic stories about blogs that failed. “You don’t hear of a lot of species going extinct, because they just fall over in the forest and die, without much of a whimper or a growl.”

Then I asked what he thought I should do the next time I felt the beckoning of the blogs. “I don’t think you have the guts,” he said.