Actually googling is harder - you have much more junk information to filter out and the deep stuff probably isn't going to be there. If you want to go past three pointing by the numbers, a book is the way to go.
And you can buy what you need on kindle a lot of the time, so you still don't have to put your pants on. The guy who did the Gaffer series on youtube recently published this on kindle -
https://www.amazon.com/Shaping-Light-Video-Age-LEDs/dp/0983707529
Together with the videos it will probably be all you ever want to know.