I have tried everything from putting ads into my books, to having great links listed but the response from my readers has been minimal at best. Through experimentation, reading, attending talks and seminars, I gradually began putting together a system that gives me a larger opt-in response from my printed materials. This idea is not new but it does need to be done on a consistent basis.
For each book I write, I write for a specific audience and therefore want to have a unique URL. My books are laced with links to get free items that are related to the book material and hopefully what I write is so enticing, the reader will take the time to go to the website and enter their email information to get the gift.
But simply having links for free information is not enough, I add other goodies to the mix in the footer of the book such as a free 7 day course on writing skills, or marketing books. Since the footer appears on every page, the reader will eventually look at it and perhaps respond. But do not stop there, you are after that name on your list so you can continually market and upsell other products. Add third party offers throughout the book as well (you should be an affiliate of the third party offer so you make additional money). The third party offers should also be driven to your URL or to another one you have created specifically for that product. There is no harm in having multiple websites that each offer one specific product - you never know what people will decide is best for them.
There is one word of caution here, you have to make sure that what you are offering is beyond all expectations. If it is, then the upsell to additional higher priced products and services will become easier because the customer knows that you deliver on your promise and beyond and they know they will not be disappointed.
If you are not ready for this approach - start with a book, lace it with incentives to drive customers back to your website, and have a prominent way to collect email opt-in information. After the book, start productizing with audio programs, workbooks, DVDs etc. It is not difficult, you just need a system that works for you and a system that keeps you on track to complete the work.
Bette Daoust, Ph. D. is a speaker, author (over 170 books, articles, and publications), and consultant. She has provided marketing, sales, business development and training expertise for companies such as Peet's Coffee & Tea, Varian Medical Systems, Accenture, Avaya, Cisco Systems to name a few. Dr. Daoust has also done extensive work with small businesses in developing their marketing, training, and operational plans. You may contact Dr. Daoust at http://BizMechanix.com You may also view her latest publications at http://BlueprintBooks.com Dr. Daoust also writes for the National Networker http://theNationalNetworker.com