Recently I have finished reading "Never Eat Alone" by Keith Ferrazzi, which is full of advice and techniques on improving your lot in life by building out your real-world social network. While I enjoyed reading this book and certainly learnt lots from the experience, I did struggle to finish it due to the writing tone of the author, which I found at times too familiar and a little self-promotional.
None-the-less I recommend it because it does contain some very solid advice and techniques you can apply yourself with a little bit of courage. You can read my full review here.
Updated 2022 : note that the above post was originally published in 2011, but is left here for archival purposes.