For those who aren't familiar with the document, it has been described as "probably the best sales manual ever written." It was one of the first things ever written by a young David Ogilvy.

It's mentioned elsewhere in this thread, but one of the best books I have ever read on advertising and marketing is Ogilvy on Advertising. If you have even a passing interest in selling anything to anyone, or just want to see how the sausage is made, I would strongly recommend it. One thin book, no fluff, with more concrete advice than ten thousand blog posts.