The Fraud Advisory Panel, which was established by the Institute of Chartered Accountants as a think-tank on fraud prevention, described e-business as a "paradise for fraud" because of the difficulties in monitoring and regulating activity.
It said the lowering of barriers to entry has made it harder to distinguish between legal and illegal players.
Specialist training in tackling cybercrime for FBI agents and law enforcement officers in the US has already shown the success that can be achieved, said the panel.
"The law needs to be revised to address both new offences and the way in which old offences may be committed using this new medium," said the panel in its annual report.
"The recent agreement by EU member states to implement the principles of the 'Cyber Treaty' is only the beginning.
"A review of the adequacy of existing legal concepts for fighting cybercrime and cyber fraud also needs to be carried out."
The panel said the connection of most computers to the Internet facilitates crimes that were previously difficult to commit. But because of users' expectation of speed when online they are intolerant of delays caused by thorough checking.