Help – How to provide Email Subscription with Free E-book on my WordPress Blog?

I notice on a lot of blog sites, there is a email subscription button that offers a free product download once they are confirmed on my WordPress blog.
Only problem is that I want to have a widget signup where I can place a picture of the book and customize the look of the widget. Any help in where I can get a plug in that will do that?
Regards,

See original post by anzilone