"Get Books" allows you to search for ebooks online, that you can then
purchase/download to your calibre library. It can simultaneously search over 40 different online stores for books by title and author. The returned list of matches can be sorted by price, allowing you to find the cheapest edition of the book. To access "Get Books", click the icon shown below in the calibre tool bar.
Parallel Searching: In the latest version of calibre (0.8.21 right now) "Get Books" searches over 40 stores from various countries for ebooks. These stores include ebooks in English, Spanish, German, Russian, Polish, Dutch, French and Italian. The search results only show ebooks and exclude paperbacks, hardbacks etc. However you do not have to search for the ebooks in all the stores. You can choose the stores to be searched by selecting them from the list on the left. In the figure below as you can see on the left column 3 stores have been selected so "Get Books" searches on those stores.
You can search for a particular ebook by entering the title in the search box or you can search for all ebooks by a particular author by entering the author name in the search box. In the figure above the search has been performed for the title "the naughtiest girl in school". One could enter "Enid Blyton" in the search box to see all ebooks by Enid Blyton available in the selected stores. It is also possible to simultaneously search for an author and title as shown in the figure below (title is "Youth" and author is "Asimov").
Price comparison: It is interesting that the price of the ebook in the
different store varies quite a bit as shown in both figures above. "Get books" allows you to do price comparisons over a very large range of stores when buying ebooks. Project Gutenberg, Archive.org, mobileread.com and Manybooks, between them, carry almost all the public domain ebooks and make them available free. So if you are looking for a public domain ebook like "Youth by Asimov", one of these may be your best option.
DRM status: Price may not be the only thing that determines where you buy your ebook from. "Get Books" also tells you the DRM status of the ebook. A "red lock" icon in the DRM column implies the ebook has DRM. This means it can only be read on particular devices so be careful to check compatibility with your device. A "green open lock" implies the ebook does NOT have DRM so you can get this ebook for any device. Even if the ebook is not available in the format you would like, you can convert it to a format of your choice using calibre. A
"blue question mark" implies the DRM status is not specified by the store and therefore not known. In the figure above Amazon has two versions of the ebook, one is DRM-free and costs $1.49 and the other has DRM and costs $0.99. Barnes and Nobles also has two version of the ebook both for $0.99 but the DRM status on both are unknown. The Project Gutenberg and Feedbooks versions on the other hand are both free and DRM-free.
For more information on DRM visit "about DRM".
Language tip: Typically if you're looking for a book in a specific language then searching for the title in that language is the best way to go about finding it. For example searching for "Adventures of Huckleberry Finn" only gives results in English but searching for "Las aventuras de Huckleberry Finn" gives results in Spanish.
Internal browser: As shown in the first figure, if the little box marked "Open in external browser" is not checked then when an entry in the list is clicked on it will take you to the sale or download page in calibre's internal browser. the advantage of using the internal browser is that if you are getting your ebook from Archive.org, Feedbooks, Manybooks or Project Gutenberg,the books downloaded directly from the "Get Books" search dialog into your calibre library; otherwise for every store, except Amazon, the internal browser detects ebook downloads and automatically adds them to the your calibre library. Books from Amazon automatically open in an external
Affiliate programs: By using "Get Books" you could help support various calibre developers at no cost to you. The various "Get Books" stores were set up by different calibre developers. Some of them have affiliate programs and there are marked with a little red heart as shown in the rightmost column of both figures above. When you buy an ebook from one of these stores with the affiliate program, the developer who set up that store gets a small percentage of your purchase through the stores affiliate program and this is at no
additional cost to you. If you want to know the name of the developer you are supporting just hover your mouse on the heart icon and a little information bubble will tell you the name of the developer. Most of the American stores are courtesy of John Schember while most of the European stores are courtesy of Charles Haley.
Something to keep in mind: "Get Books" aggregates stores from all over the world and while it may present results this doesn't necessarily mean the store will sell to you. Many stores (pretty much every one employing DRM) have geographical restrictions on who they can/will sell to. Get Books only tells you who has it and for what price; it doesn't tell you if the store is willing to take your money for the book.
I would like to thank calibre developer John Schember for his help with this article and for the instrumental part he has played in the existence of "Get Books".