First stop: Amazon Books, where you’ll find summer reads for everyone in your crew and — surprise! — sunscreen, too. Light and non-greasy, Supergoop Play Everyday Sunscreen ($19) will be an instant favorite. Formulated specially for babies, the Babyganics Outdoor Essentials Pack ($19.99) includes both sunscreen spray and insect repellant. And pick up a copy of “The Little Book of Skincare” ($24.99) for expert tips on suncare and more.