How to create professional looking ebooks(or what tools/service do you use)?

Hey guys, I'm about to make a ebook as freebie for my opt-in page, well after searching for quite a while, I found that it's way too expensive to hire a designer to do the job, but I do want the ebook to be a professional/good looking one, so is there any shortcuts/good tools for this job? Or would anybody recommend some good services which don't cost much?

Thanks