This is the most obvious place. They generally have a whole section of audio books and though they generally do not allow them to be taken home like other books, you can enjoy listening to them in a library where the atmosphere is also ideal for the purpose. Find yourself a nice seat in the designated area and listen to your favourite books being read. The libraries generally have a great sound system installed which makes the listening experience all the better.
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There are many websites that offer books online. Not all of them do so legally but not all of them do it illegally either. You can find a reliable website that offers free audio books legally and enjoy listening to them. You may not find all the books that you want to listen to free of cost as they may charge for newer and more famous books but you can still enjoy a wide range of books to choose from that are not being charged for.
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Smart Phone Applications
There are certain smart phone applications that offer audio books free of cost. You can download them or have audio streaming done if the option is available and you have a fast enough internet on your phone.
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