Police obtained a search warrant to seize property at the home of Gizmodo’s Jason Chen, who had obtained an iPhone prototype. The search is a test of California’s shield law for journalists. And it gave Jon Stewart a chance to tell us how he really feels about Apple. And Steve Jobs. And AT&T. And Paul McCartney …

What exactly is an investigative journalist?

Is a journalist someone who does the tedious work of digging through records, analyzing data, and finding good human sources to ferret out the truth?

Or is a journalist someone who dresses up like a pimp, straps on a hidden camera, and tricks workers at ACORN to say really dumb things?

Filmmaker James O’Keefe went the easy pimp route. Last summer, O’Keefe shamed ACORN workers in an undercover video, and O’Keefe’s conservative supporters praised his tactics as real shoe-leather reporting that has been neglected by the mainstream media.

But investigative journalism is not a publicity stunt. It’s not a gimmick. It’s actually tedious, time-consuming work. And more people are beginning to understand that — thanks to one of O’Keefe’s recent stunts.

O’Keefe and his pals were recently arrested for dressing like phone repairmen and infiltrating the office of Sen. Mary Landrieu in a federal building. After the arrest, even conservatives started raising questions about O’Keefe’s methods. John Hood at National Review Online put it this way:

Whatever you think of these kinds of publicity stunts, they do not constitute investigative journalism. The earlier ACORN videos weren’t pieces of investigative journalism, either. It does the growing ranks of investigative journalists at conservative organizations a great disservice to invite a comparison of such publicity stunts with the hard, meticulous, and often boring work of exposing government waste and corruption.

The New York Times published a Sunday story pointing out O’Keefe “is just one of a group of young conservatives who use political pranks and embarrassing recordings to upend what they view as overwhelming liberal biases on college campuses and in the culture at large.” Jon Stewart at the Daily Show said it seems like O’Keefe gets all his story ideas from porn movies.

Instead of dressing up like a pimp to make a splash, why not dig up records to find out what’s really going on? That kind of work might seem boring to people like O’Keefe. But to the reporters who actually do this kind of work, sifting through documents, putting together the pieces of a puzzle, and discovering something no one else knows is rewarding and worthwhile.

Give it a try, James. You might be surprised at the real stories that are out there.

Update: It turns out O’Keefe wasn’t even wearing pimp threads when he went undercover at ACORN offices.

The Daily Show’s visit to the New York Times was hilarious — “The spinning — always the spinning. Let’s see you do that, computers.” But one of the editors could have given a better answer to Jason Jones’ question about why “aged” news is better than “real” news.

Jones handed assistant managing editor Rick Berke a copy of the Times and asked: “Give me one thing in there that happened today.” Berke got flustered, which was understandable with the cameras on him. The correct answer was: Nothing. Nothing in the paper happened today — but look at all the in-depth stories in the newspaper that connected dots and explained to readers what was really going on in the world.

A prime example: the Pulitzer Prize-winning stories by David Barstow, who won the prize for “his tenacious reporting that revealed how some retired generals, working as radio and television analysts, had been co-opted by the Pentagon to make its case for the war in Iraq, and how many of them also had undisclosed ties to companies that benefited from policies they defended.”

That was “aged” news. But so was Watergate. It was important information that took months to uncover and needed to be told.

Watchdog journalism keeps newspapers relevant. Yeah, it’s aged. But those are some of the best stories out there.