Recruiting professionals rather than anybody who will listen is the argument Duke Romkey keeps returning to, and it changes who you approach and how. His case is that somebody who already sells for a living needs less teaching and quits less often, which sounds obvious and is almost never how people actually recruit.
His second argument is stranger and better. He says lasting success in this industry belongs to whoever owns intellectual property rather than to whoever holds a rank, because a title depends on a company and a body of work does not.
He is blunt about the skill itself, with a post on what terrible recruiting actually costs you and how to measure the improvement.
Around that sit affiliate posts on checking that you are credited for every order, and a piece pulling lessons out of a night of famous advertisements.
Read the intellectual property post. It is the one that will still matter after the company does not.