I swear to you that's all I can find. Win the Newbery and your name gets plastered across a million websites - all focusing on the book instead of the author. Regardless, here's what she wrote:
Books:
El Guero: A True Adventure Story
I, Juan De Pareja (1966 Newbery Award)
Leona, a Love Story
Yo, Juan De Pareja
thanks to:
http://www.bakersfield.com/2000/kernlife/individualsofnote.htm
www.amazon.com