From the “nothing new under the sun” department, I just found RepeatAfterUs.com. Says the about:
RepeatAfterUs.com was founded by Ellie Wen during her sophomore year at Harvard-Westlake High School in California. While volunteering at Las Familias del Pueblo, a community center in downtown Los Angeles, Ellie saw individuals struggling with pronunciation in an English as a Second Language class. She decided to build a website that would provide free texts and audio clips to help students around the world with their language skills. Through the efforts of other students and faculty, RepeatAfterUs.com has become an award-winning, critically acclaimed online library and language lab.
Amazing that it took me so long to find them, they seem to have been around since 2003. Well congrats to Ellie and her crew on being, without us or them knowing it till now, an inspiration to LibriVox!