I got this info from Amazon. Most libraries now offer ebooks. You have to have a library card to your local library and once they set you up with a pin you can check out ebooks online. I use both the county library and the city library to check out ebooks. If you have questions most librarians are really helpful and can walk you through it.
This information is copy and pasted from Amazon:
Borrow Books from a Public Library
More than 11,000 libraries in the United States offer Public Library Books for Kindle. You can check out eBooks through the website of your local library and have them sent directly to your Kindle device or reading app.
Kindle books that you borrow from a public library are available to you for a specific period of time, just like with library books. Public library books for Kindle are available at libraries throughout the United States. These books are offered through a digital service called OverDrive.
Note: Public Library books for Kindle are available in the .azw Kindle Edition format only.
✦Check Out a Public Library Book
• You can read borrowed Kindle books on any generation Kindle device, all free Kindle apps, as well as in your web browser with Kindle Cloud Reader.
• Confirm whether your branch is eligible and carries Kindle eBooks, visit Overdrive or the website of your local library.
• Get a library card and a PIN from your local library.
Note: At this time, public library books for Kindle are only available at U.S. libraries.
✦Restrictions:
• Availability of books and length of loan will vary by library.
• Public library books require an active Wi-Fi connection for delivering books to a Kindle device. Library books can not be delivered via your Kindle’s 3G connection.
• Due to publisher restrictions, some titles may not be wirelessly delivered and require USB transfer from your computer to your device. These restricted titles also may not be accessed on Kindle reading applications.
• Go to the website of your local public library and search for eBooks.
• At checkout, sign in to your Amazon account, and select the device or reading app to send the book to.
• Connect your Kindle to Wi-Fi. If Whispersync is enabled, your Kindle should receive the book automatically.
• If your Kindle does not receive the book, sync your device manually.
✦Return a Library Book
• To return a library book before the loan period ends, visit Manage Your Kindle.
Since the length of a book loan is determined by the library, check with your public library to find out when to return a borrowed book. You’ll receive a courtesy reminder e-mail from us three days before the book is due and another email when the loan period has ended.
• Visit Manage Your Kindle.
• Next to the book that you want to return, click Actions, and then select Return This Book.
You will no longer have access to the book from your Kindle. However, you can always access your saved notes and highlights through Manage Your Kindle even after the book has expired. If you check out the book again, or purchase it from Amazon, your notes and highlights will appear in the book.
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