Where do babies and credibility come from?

I like Usman's answer (+1!), but here's how I did it:

I wrote a book. 40,000+ copies in the field, and it's very technical.

People still react to the power of a physical book. Not an eBook, not a whitepaper, but a real, physical book. Books are sacred. Books aren't thrown away. Even though self-publishing is easy nowadays, people react as though it were published by McGraw-Hill.

It's possible for you to do it to because:

1. I wrote it in Word. No special tools required.
2. It's 164 pages, but really small ones (outside dimensions 5x7, but then there's gutter for binding, margins, header/footer, etc.). So it just took two months to write all the text.
3. Self-publishing is easy. I used http://48hrbook.com because I needed to be able to distribute the book myself (you get a free copy shipped to you if you fill out a form on our website -- amazing lead-gen by the way!), but if you wanted to charge money I recommend http://lulu.com because they do all the fulfillment for you and you can offer both a physical and PDF version at two different price points.

Probably the best way to start is to write whitepapers (for formal documents) and a blog (for everything else) and later cull it into a book. That way you get all the usual benefits of those documents and of working on the project incrementally.