Book
I wrote a short book about the Web Audio API called "Web Audio API: Advanced Sound for Games and Interactive Apps".
This book is what I wish existed when I started experimenting with the API in 2011. It is intended to be a springboard for web developers like I was, with little to no digital-audio expertise. It contains the things I learned from about a year of studying digital audio processing, having conversations with audio experts, and experimenting with the API.
O'Reilly published it, Amazon sold it, and I released it for free under the CC license. It's available in a few formats: