You work with them now, have worked with them before (or know someone who has), you've read their blogs, tweets, and books.
You know more about them than a recruitment agent or website can. To you, the best are only an email or tweet away.
Use PoachList to keep track of the people you want to work with - the people you'd hire right now if you had the chance.
Why bother with recruiters, resumes or LinkedIn? Start a poach list today, you never know when you'll need it!