The packages, which are advertised as new and original, have been offered in a series of major sales over Web auction sites over the past few months.
Some auctions have offered up to 2,000 premium business packages at a time, including Microsoft Server 2000, Office 2000, Visual Basic, and Adobe Photoshop, Computer Weekly has established.
The auctions have caused alarm among small businesses, who often use the Web as a time-saving way of buying software and other essentials.
"A lot of our members are using sites like this. They haven't got time to go out shopping for software. We will be raising this with the e-minister Patricia Hewitt," said David Hands, director of the Federation of Small Businesses.
Sellers have been able to protect their identities by hiding behind false names and using temporary free e-mail addresses to communicate with buyers.
One auction site, QXL, has received complaints from more than 30 customers who said they have been duped by software pirates into buying poor quality copies of Microsoft and other well known business packages.
Users claimed that QXL has not identified and closed down pirate software auctions quickly enough to prevent them losing their money.
One customer, who asked not to be named, said, "They are probably not as bad as some sites, but, given that people are spending money online, they should be more responsible."
The Business Software Alliance, the industry group which campaigns against pirated software, examined an Adobe package bought by a QXL customer for Computer Weekly. The package was advertised as original.
"We are 100% certain that this is not a genuine Adobe product," said Margo Miller, the BSA's European counsel. "Anyone buying it would not be able to use the product legally and would not qualify for back-up support from Adobe," she added.
The BSA, which estimates that up to 80% of the software sold on online auction sites could be pirated, has criticised sites for failing to effectively police themselves.
The BSA is developing a set of guidelines that will help online auction sites spot the tell-tale signs that could identify fraudulent software.
QXL said it takes care to protect its customers by monitoring sales on a daily basis and closing down pirate software auctions as soon as they discovered.
The company said its investigators pay particular attention to auctions by people who use anonymous e-mail accounts or give mobile phone numbers as their contact point.
Customers also have the option of paying a small fee to join QXL's "safeship" service, which ensures that sellers are not paid until customers receive the goods.
"We do try and make it very clear under our terms and conditions to both buyers and sellers that pirated software is illegal," said a QXL spokeswomen.
Catherine Taylor, UK marketing director of Yahoo, said that Yahoo worked very closely with industry groups to ensure that it does not break the law.