LIVE OAK - Peaches are in season, and Leticia Lopez has just spent six hours doubled over a bin, picking out the misfits. Lopez came to this small town north of Yuba City about a year ago, leaving five children - ages 3 to 17 - in Michoacán so she could earn money for them here. The 34-year-old widow finds it difficult and frightening without her family and without papers. She would prefer to be here legally, but economic realities compel her to stay. In Mexico, Lopez made about $15 a week cleaning houses and washing clothes. Here, she makes...