If you purchase your books off of Amazon then there is an easy way to get them from Amazon into your Goodread account. While it is easy to do, if you organize along the way then it may still be a time consuming process.
Click on My Books on the upper top of Goodreads
Scroll down until you see Add Books to Goodreads. Under this click on Amazon Book Purchases.
Once you get to this screen you will see all book purchases that you have made through Amazon. It will include all Kindle and paper version of books. Once a book has been included on a shelf in Goodreads then it will no longer appear on this list.