You can now create personalized libraries on Google Books.
Create your own library and add book reviews and ratings on Google Books
Label, review, rate, and of course, do full-text searches of a customized choice of books.
More details and step-by-step instructions on setting up your Google Library are available on the Google Books help page.
Some books are free to access, save to your library and read. Others are not.
You can preview pre-selected pages before purchasing.
I don’t use the Amazon Kindle product, but I do buy physical books on Amazon. Amazon’s book preview is comparable to Google Books preview, although Google Books offers at least 20 pages as a preview. Amazon usually displays only the front and back covers, table of contents, and a few pages of text. Google Books are available as a PDF or EPUB formatted file after you pay using either Google Checkout or PayPal.