I've edited and published a number of books in the last few years.
Mainly because my research was coming up with all these books in the public domain which couldn't be found in bookstores (or had really bad cover art and formatting). I found many books online in HTML and in PDF format (also with bad formatting).
Since I thought I could do better, I worked out how to do so - and here's the technique.
Overview: HTML --> Adobe Acrobat --> NoteTab --> OpenOffice --> Lulu
1. You publish on Lulu, since this is the cheapest and best route for publishing. Authors do their own marketing, even if a "big name" publisher signs them to a contract and "gives" them a commission. Lulu requires PDFs - and gives you templates to use (.doc) to build and submit your book. (They even give you cover art templates - both front and back...)
2. So, you have an HTML file - or several of your book. Say each chapter is its own HTML file. Get a copy of Adobe Acrobat (not Reader, the real thing). I prefer Adobe Acrobat ver. 7. Here you can create a PDF from each web page. Then you combine all these pages into one. document. Save it to your hard disk as a PDF (backup). This also goes for combining existing PDF files (just make sure you have unprotected copies).
3. At this point, you have all sorts of interesting formatting going on, with lots of links and so forth. Follow closely here - there's reason to what I'm going to tell you. Now take that single file and save it you your hard disk as HTML 3.2 - yes, you're converting it back into HTML.
4. Now open that single HTML file in NoteTab (a free download). This program has an option to remove all HTML tags - which is handy. Then you can search for and replace all sorts of extraneous stuff. Get this file as clean as you can, since their search-and-replace function is more powerful than Open Office.
5. When you're done here, save as a text file. Open that text file up in Open Office and use the template Lulu gives you. In Open Office, you can import styles from another document - which makes it easy to keep the same formatting from one document to another. Then when you're happy with the way the document is set, export it to PDF.
6. Proof your PDF, correct any errors in Open Office, then re-export until you're again happy with it.
7. Now, logon to Lulu and publish your book, uploading your PDF when requested.
I use Open Office because it's free and its not Microsoft. They update it regularly and is actually a better product than MS Office or similar.
You could always open up each separate document in NoteTab and copy/paste them all together into one document. But importing them into Adobe is faster and has less chance for error - as it keeps bookmarks on all documents imported, so navigation and editing is easier.
Oddly, when you then have to then get it ready for Amazon, you have to make it into an Adobe distilled file - which loses an incredible amount of functionality for the download version.
My best strategy to date: Use Amazon as a loss-leader, bringing traffic back to Lulu - which will give you much higher royalties (like 4x or more). Most of my traffic in Lulu has been downloads, which is just fine. It will be interesting to see a) if the Loss-leader strategy works and b) if hardcopy sales ramp up.
How to drive people to Amazon (and Lulu) will be Article Marketing and Autoresponders. When you "release" a book to Amazon, you simply then offer a limited-time offer to your list - bribed with various additional books (which cannot be easily obtained otherwise) and MP3's, etc. This is, of course, per Joe Vitore - who's already been there, done that.
My approach is to create a body of works first and then start marketing these bit by bit - creating a circular/spherical world of works which all inter-relate. So you don't just buy a book, you get - ultimately - the whole reference library.
But that's the point. While there is more than one path up the mountain, no one school has all the teachers, all the lessons.
The trick is to get it all done in one lifetime.