Your sporting clays bibliography?

Most of the best folks these days eschew books and push DVDs so you can get a visual. Along those lines, Gil and Vicki Ash OSP, Derrick Mein, Anthony Matarese, Jon Kruger, Dan Carlisle, and a host of others........

Edited to add:

One book I DO recommend is The Stockfitter's Bible by Rollin Oswald. Shotguns are all about FIT, and this is THE bible to learn about that

In addition Rollin is a super nice guy. He is a member at Shotgun World and I sent him a PM once asking if I could call him and ask some questions. He sent me his phone number and when I called he spent a good while talking with me and told me to call him anytime. This was around seven or eight years ago.

As George notes, books aren't really the thing these days. I find Chris Batha very helpful. Lots of his stuff available online.

A long time ago a fellow clays shooter, on deck, was watching me shoot clays. He had recently attended a 10 day clinic on fitting stocks and shooting clays. He offered to check my fit at his home shop on our way home from the range. He had bought all of the measurement tools the clinic he attended offered. I found out that my idea of proper figment and actual proper figment were two different things. Long and short, if you have never had a competent stock person check your figment, do so.