I've found that formatting for different ereaders is hands down the hardest part of publishing your book online (once the book is written!). Without a good deal of expertise in html and coding in general, it can be impossible for authors to make their eBooks look anything like the original document. Pictures can pop in and out of existence, page breaks and titles loose any sense of complacency, and that's before you try to add a table of contents.
There are companies that offer to format your book for you, but they charge no less than $150 for one book. So if you have a friend or family member who can manipulate html, I'd ask them for help. If not you're left with two options.
1. Download several programs, like amazon's free "kindle previewer" and get to work. It may take a week or two to work out the knots in your ebooks design, but any book can be tackled with enough persistence.
2. Go to my site at [site edited] I've been personally converting books for authors for a few months now, and with great results. I even have a gallery of completed conversions so you can see exactly what you're getting. If you want your ebook online and looking good, I'm your man