This is a screen shot of AudioOwl's main page
AudioOwl's mission is to make "the world's public domain audio books available for browsing in a visual and entertaining way...AudioOwl puts the fun back into browsing for audio books. For those who listen to audio books because reading does not come easily to them, the last thing these people would want to do is read through pages of text to find something to listen to. AudioOwl provides a primarily visual browsing experience so you don't have to read tedious amounts to find listening material."
This is a screen shot of the page for Children's books
All these audio files can be found in other places on the web - Librivox.org, or the Internet Archive, among others. "The majority of public domain books, however, are digitized by Gutenberg.org and recorded by Librivox.org. AudioOwl draws on these public domain sources to deliver free audio books to you in an engaging and fun way."
All these books are in the public domain - that means their copyright has expired, and that means (usually) that they are "old" and "classics", but it doesn't mean they're not worth listening to! You'll find some of the language old fashioned, and probably you'll like some of the readers better than others. You can look for books by genre, and by language. This is definitely a resource worth exploring.
This is a screen shot of the page for Johanna Spyri's Heidi kann brauchen, was es gelernt hat