The IRS has taken upon itself a task no one asked it to do: regulate small, independent tax preparers. And like any federal regulation worthy of the name, its rules are byzantine, unnecessary, redundant, legally dubious, and hostile to free enterprise. The rules require anyone who accepts payment for filling out income-tax returns to register, pay fees, take special tests, and complete annual continuing-education requirements. Special interests, writes A. Barton Hinkle, will be exempt from the rule.