The Bean Trees by Barbara Kingsolver

[Bam cooks the books]

Taylor leaves her childhood home in Kentucky, driving an old VW, with a plan to drive west till the car breaks down. She makes it as far as Tucson AZ but along the way, she has acquired a 3-year-old Indian child. I believe this was Kingsolver's first novel written in the 80s and it's quite good, dealing immigration issues.