I have lots of free Kindle books. I have discovered some marvelous writers that way. I have also downloaded some pretty awful (in my opinion) books that way. At least with free books, you aren't out any money if they are bad.
With few exceptions, I purchase books for less than $5. And there is a Deal of the Day where a book (sometimes a few books that are related somehow, either by the same author or of the same genre or whatever) that is discounted. Some just happen to be books I have been wanting to read anyway.
Some libraries offer Kindle books for loan. I know the library in the next town over does this, but I haven't checked to see if the one in my town does it yet.
Books can also be loaned to a friend or family member, but for now, the book can be loaned only once and for only 2 weeks, then it goes back to you. I have done this once, when I loaned a book to my mom.
Eastern time zone (USA) (We will be on DST from March 10 to November 3, 2013.)
Motivational Leader (ML) for Casual Travelers.