One of the decisions you have to make is how much you're going to charge for your book. Like everything else I did some research on this - by looking at the prices of other books, and reading other people's thoughts on the subject.
I decided from the outset I wasn't going the 'free' route, which incidentally you can do on Smashwords, but not with Amazon. The minimum price you can set with Amazon is $0.99.
If you are selling the first book of a trilogy or series, I can see that hooking new readers by selecting 'free' has some advantages. Lives Interrupted is a standalone book, and while letting it go for nothing might give me some readers for the future, I believe it is worth something.
There is plenty of anecdotal evidence, and comments from other authors, on the best price to set. Some say between $2.99 and $4.99, while others between $0.99 and $2.99.
I decided that $2.99 was a fair price for my work. Not only did I put a lot of effort into writing Lives Interrupted, but also in making sure it was as perfect and error free as I could make it.
Time will tell whether that is a reasonable price. Watch this space and I'll let you know.