The Emacs welcome screen links to a tutorial, a guided tour, and manual, all of which are inside Emacs. I would say its help functionality is potentially its greatest strength.
Dude, incredible work. I've only discovered CL in the last couple of months and everything I learn and discover brings me so much joy after being solidly disillusioned with programming after a decade-ish career. The first page of your tutorial cracked me up and a quick glance at CLOG has blown my mind. I can't wait to dig into it all.
Microsoft's interview loop was the easiest I've ever had, it's the only job I've had where I've felt my ethics challenged, and my org's leadership was comically ruthless.
You joined a good org and that's awesome, but I believe you can just as easily join a bad one at Microsoft or a good one at Amazon.