Lists come from bylines: who has covered this topic in the past ninety days, at which desk and from what angle. Tools like Muck Rack and Ahrefs help surface the coverage, but checking is manual, because a pitch to the wrong desk burns goodwill.
The pitch itself follows a shape. The subject line reads like the headline the journalist would run, the first sentence states the story, two or three proof points follow, and the close offers the full data, images or an interview. The whole email fits on one phone screen. We send one follow-up a few business days later, only if it adds something new, such as a fresher stat or a regional cut. If that gets silence, the answer is no, and accepting it cleanly is why the same reporter opens the next pitch.