Starts with email, sometimes moves to phone. It's hard. Sometimes people are jerks and you have to get used to rejection. I find that my success rate is dependent entirely on my pitch, so I spend a lot of time refining that. And yes, I've secured link placements doing this.
It's tough because it's not truly template-able in a one-size-fits-all pattern. The latter success came because I identified some webmasters who monetize guest posts and will take anything quality. The former was cold outreach to people who are historically bad at technology, and I'm convinced they don't actually know they have a blog.