Welcome to the forum.
If you do a search for 'selling ebooks' and 'marketing ebooks' you'll find loads of information. Some of the information/advice is good, some bad. As with anything when they promise that you'll make cart loads of money sounds too good to be true it is too good to be true.
"how the book is published?"
Most often ebook publishing means distribution through the Internet. Some ebooks are too large for download and the publisher releases the ebook on CD-Rom.
"does it require a fee?"
Some ebook compilers do charge a fee, most don't. The reason for the fee is related to the security system imposed on the ebook. Each ebook compiler has a different approach to making your ebook secure from being unlawfullly redistributed--some offer no protection at all.
If you do a search through this forum you'll find several threads concerning ebook security. Before making a decision on which ebook compiler is the right one for you decide on how you intend to market. The two main apporaches are: 1) payment is required before the ebook is downloaded; 2) the ebook is downloaded with a few sample chapters unlocked. My preference is for method two because I want the user to pass a copy of the ebook on to friends (known as viral marketing) and Activ's security system minimizes the registration codes, used to unlock the ebook, from working on two computers (the probability is 0.1%).
"what is the mode of transaction?"
Again, search through the forum for additional information. Finding a method for collecting money isn't the real problem (there are many services that will provide that will help you.) The real problem is what happens after the transaction is made. This is where the type of security system you use becomes important.
The choice is that you can use a fee service (or write your own if you know PHP) or use software program that has a one time fee. Basically what happens with the fee service is that after the ebook is purchased the user is sent a link to where they can download the complete ebook.
The other method (the one that I use) required a one time purchase for a system that allows the user to pay for the ebook, then immediately be given a registration code to unlock the ebook.
Of the two methods I prefer the second because: 1) The ebook is known to work on the user's computer. 2) Completion of the sale is immediate. 3) The user is not required to endure another download. 4) The ebook can be shared with a friend, but the friend will still need to purchase a registration code to look beyond the free demo pages. 5) Reduces charge-backs because the ebook is already working on their system and they are using the same ebook that they previewed the demo pages.
"is there a market for medical ebooks?"
This one you'll have to research. Who is your intended audience? Medical professionals? ???
"is there any free software?"
Are you interested in free software or the best software to accomplish your objectives? For me I focus on my objectives, then find the right tool for the job.
Every now-and-then, I'll reevaluate the software I'm using. Not that I'm interested in the latest bells and whistles, but what makes the job easier and/or accomplishes my goals. Recently, I reevaluted the ebook compiler that I've been using (it's been Activ eBook for some time now). What I found is that for my purposes Activ is still the best compiler out there. Most of the others were eliminated because they either didn't have any theft prevention or if they did it required a fee of some sort.
Most of the ebook compilers have a demo version. Try them all and see what you think. The thing to check out is how the ebook is made secure and the hidden cost to do so. You won't find a hidden cost with Activ. Do a search in the forum and you'll find several threads related to the subject.
Your questions are always welcome.
(Edited by Storyman at 11:28 am on July 25, 2005)