I recently bought the Ultimate Link Building Dossier, by Duncan Carver. He has been a full-time internet marketer for 10 years and has done a marvelous job at revealing this process of link building. He covers everything from article marketing to social media to directories to videos.
What I like best is that it is designed to work and save time. He also provides a strategy so you stop wasting time.
Link building is 95% of getting a good SEO result and I've been focusing on the 5% way too much! Very well worth the money.
See the Ultimate Link Building Dossier