The author, Billie Letts, was an Oklahoma girl, an English teacher, and spent years writing stories and screenplays, and collecting rejection slips.
When she retired, she signed up for a writers' conference in New Orleans and ran into a writers' agent who was interested in seeing her work.
Billie sent her several things she'd written, including the opening of Where the Heart Is. She also attached a note, saying that the story of the young girl broke, pregnant and locked in a Wal-Mart late at night in a strange town just "wouldn't let her go."
The agent read the short story, read the note and then called her up and suggested that she might just have a novel on her hands. She did. It is, and one of the best I've read in years.
I didn't see the movie, but the novel is a wonderful work. I'm sure you'll like it. The story is fiction, but it feels honest and like it could be real.