The posting links to the blog post about the tool, but if you click on Mac Monitor at the bottom of the page under Products and Solutions it takes you to the actual page for the tool and that page has the big red download button everyone is talking about..
I clicked the subtle 'Red Canary Mac Monitor' link at the start of their news text. I couldn't find it from their homepage either.
I kinda felt the big red 'Download package' button gave it away?