This is a good idea. At the most basic level this is literally a case of watching the parking lot of journalism outfits, then following the reporters vehicles if they leave during the day, getting out with signs and standing behind them holding placards whenever they try to film. If they still actually do that? With more manpower these buildings could be picketed, to lawfully harass them on their way into work. If you got them on the way in and were there wherever they went, that would change their perceptions and get the message out nicely.