The modern way of marketing a book is to use a book trailer. You can post it on your website directly or better still upload it to YouTube then embed the video on your site.
The advantage with Youtube is it is vast and visited by millions of people many looking for book trailers in your genre. The main disadvantage with Youtube is it is vast and your trailer has to compete with millions of other videos.
Having said that if you properly title and tag your videos you can get high search engine placements. With proper promotion and right video, you will maximize online viewership and increase your book sales.
So armed with little knowledge, Photoshop, Poser and iMovie you can set to work. Even if you only have a vague idea as to what you want to end up with you can start with creating your characters in Poser. Once the characters were produced you can add some simple animation using the poser animation facility.
You can then make up a few backgrounds again using Poser (or DAZ3D) then import them into Photoshop to add some static text. Once you are happy with your characters and backgrounds import the lot into iMovie. (PC users have Moviemaker).
You then use iMovie to add transitions and flying text over the characters. Move things around and adjusted the timings until you have a passable book trailer.
If you plan ahead and make up a storyboard before you start you should get your trailer to flow better and be able to combine the sections without too much trial and error, the choice is yours.
The final element is a sound track. Search the web for royalty free sound tracks. I personally wanted something dramatic like an action movie theme. I eventually found one I really liked at a cost of cost $19. The download file consisted of four 30-second royalty free sound tracks that were designed to be looped.
Adding the tracks is an easy drag and drop exercise. Search the web for some free sound effects and once it is put together you will have a passable book trailer.