You really can't. I have been looking and I found a few sites that used to have them but removed them and nothing current.
You can get all of them online, but you need to really search!! Put in the title of the book, such as " dead as a doornail PDF in google
Type scribd into google or yahoo and go to the site. Type in the name of which book you want to read (Dead until Dark is the first), and then the author (Charlaine Harris).