After numerous track days, a couple of schools and 17 years of riding I thought it was time to go read the famous Keith Code books, "A Twist of the Wrist" and "A Twist of the Wrist II".
If you're going to do track days, or racing, of any sort frankly, then I wholeheartedly encourage you to read these two books. I've thoroughly enjoyed them, and I know for a fact they've taught me plenty.
Some of the lessons/skills/drills are simple and you already do them, but even in those cases you'll probably find a way to do them even more effectively after reading the book. It's certainly changed how I'll approach each session on the track.
You'll learn stuff about bike dynamics you might not have known, and you'll get a deeper understanding of why things work the way they do.
Anyway, if you're ever thinking "Are they worth it" - I paid $26 for the set on Kindle on my phone and it was entirely worthwhile.