It's so fascinating to me when people ask how to find editors. Journalists are notoriously addicted to Twitter. Not only are they very discoverable by doing a search for their name/job title with "+ Twitter", many of them are also unable to not reflexively reply to someone who follows them on Twitter. Or even if you don't follow them -- just read Glenn Greenwald's feed and look at how many randoms manage to get his attention.

That said, it's hard to do a pitch via Twitter. I'm just saying use Twitter as a way of getting acquainted. And honestly, reading someone's Twitter feed helps you understand a bit about their personality and where they are coming from, which again, is helpful knowledge in any cold call situation.