I was thinking about giving away a free ebook as a way of getting my name out there and create viral marketing, but I wasnt sure whether it would work or how to go about doing it. Any thoughts?

If your book is good enough to get a decent price for it you have to ask yourself what the trade off is. If the book is a teaser to a larger product then it makes more sense if the book is the product I would not encourage it. You would be better off taking excerpts from the book and putting them on article repositories.

If you do give away the book make sure that in the legal disclosure people are allowed to distribute the book freely providing that they do not change it. It is worth getting Adobe Professional edition so you can put the proper security constraints on it.

I think it is worth a shot if it is something that you can put together that does not take that much of your time. The key question for you will be how do you track how successful this strategy was. Will you be able to isolate the traffic you get from this effort or the sales? If not you may want to rethink it.

If you do it make sure it is part of a broader marketing campaign. One thing that I have seen done sucessfully is that you could develop a series of short ebooks all related. The first book would be a tease to encourage them to pay for future books.

I tried this once and it was a waste of time, I would try to find another way to advertise you business. You may want to take the time to write a newsletter instead you will get more bang for your buck.