Elements of Nonfiction Introduction

Some writers of this type of book also include a short biography describing their own experience with the problem that the book addresses, and overcoming it. If you used something like that you would probably want to mingle it in with why the target audience would be interested in your book. Without going into detail, and if you think it's helpful, you could include a brief "road map" of where you're going to take the reader with the book, and/or suggestion about how the reader can use the book (some books need to be read cover-to-cover, others can be used more like a reference book).

And as for your number 3, please err on the side of it being too short rather than too long. I've read a few long introductions where I felt I didn't need to read the book afterward.

Sorry, Doomie, I saw your question yesterday and assumed someone else would answer it. I write fiction and am familiar with the preferred formatting of short stories and novels, but not with nonfiction formatting. I would guess that an introduction starts half-way down the page, but I'm not sure. In any event, I don't think this is a "biggie" as far as agents are concerned.