I came across a reference to the Blending tool; I can't find it in the Tools Panel. Where is it? Is there such a tool?
I believe they were talking about the Gradient tool (Shortcut - G). Throughout the literature you will also find it referred to as the Blending tool because of its role in creating composite images. When combined with layer masks, the Gradient tool allows you to create composite images which are natural-looking, i.e., it allows you to blend separate images into one in a seamlessly way.
Elements 7,10,11,12,13,14,15 - Photoshop CC 2017 - Lightroom CC 2015 Windows 7 Pro & Windows 10 Pro