"There was a lot of material," he said. "It was hard to filter the rubbish to find the odd nugget and it was not easy to follow in a clear fashion, which led to more confusion. You then seek other products for more clarity."
After spending a few thousand pounds, Mr Daniel cancelled his subscriptions. "I was not convinced," he said. "The whole system is designed to grab people's money."
It's often unclear what expertise many internet marketing gurus possess. Mr Haria, Ms Staar and Mr Cornish did not respond to requests for comment.
"The people making money in internet marketing are selling courses and other add-ons," said US-based blogger Jason Jones, who runs a website called Salty Droid, which seeks to expose what he claims to be the many falsehoods perpetuated by the industry. "The whole thing is fake."
A quick trawl through the testimonials on many internet marketers' websites suggested a bizarre phenomenon. Some of the students who attend courses on how to get rich online then start selling courses - on how to get rich online. Meanwhile, some of the material sold by some internet marketing coaches is what is known as private label rights - recycled content written by another author and then packaged up and resold.
"Internet money making is the great delusion of our time," Mr Jones said. "No one is making money online with the exception of the corporate behemoths - Amazon, eBay, Google etc - that cornered the market early, as well as a few porn sites. How is it then possible for a workat-home mum to become a millionaire?
He added: "The whole internet marketing industry plays on people's ignorance. The offer is always the same: there's this cool area of the web where all the growth is happening that you need to find out about - but it's never very specific.
"People are often lured by a free product like an ebook or a webinar, but this is only the beginning of the funnel, the aim is always to get you to buy two-day seminars or year-long mentoring programmes that can end up costing people tens of thousands of pounds."
It's common for internet marketing operations to share customers' details with other businesses in the selfhelp industry - via affiliate networks - to try to squeeze more money out of people, Mr Jones claimed.
"People can end up investing thousands, and when they struggle to make a profit they often blame themselves for somehow not getting it," he said.
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'You can make six figures' - we test internet marketing claims