The series kicked off this week with 5 titles, all focused on baking, including recipes from leading chefs and baking brands like: The Great British Bake Off: Showstoppers by Linda Collister, Brilliant Bread by James Morton, and The Primrose Bakery Book by Martha Swift and Lisa Thomas.
The ebooks do not appear to be available elsewhere (I checked), making this a true Sainsbury's exclusive. Tim Lennox, managing director of eBooks by Sainsbury's commented: "The Bite Sized eBook range aims to showcase some of the most successful cookery products on the Random House list and on our website, while enticing consumers to try out some of the recipes featured within these books, at a very reasonable price."
On a related note, this is actually Sainsbury's second exclusive with Random House. Back in August Annabel Karmel, a RH imprint focused on infant and children nonfiction, announced a similar exclusive deal with Sainsbury's for a line of £4.99 ebooks.
Sainsbury's has been in ebooks ever since they bought the social ebook community Anobii in June 2012 for £1. In January 2013 they launched their own ebookstore, eBooks by Sainsbury's, by taking over and renaming Anobii's beta site, which was still under development at that time.