Books (covers link to Amazon)-
Tailoring by the Editors of CPI
This book is really great. It has a lot of information presented in a great way that lets you make a jacket step-by-step. This book has been the most helpful of all the ones I've looked at.
Couture Sewing: Tailoring Techniques by Claire B. Shaeffer
This book is really geared more towards women's tailoring, but it does have some neat tips and tricks for things like pockets and bound buttonholes.
The Victorian Tailor by Jason MacLochlainn
Great for more historical stuff like I'm doing! Period techniques and patterns.
With the demise of Greenberg and Hammer it's really hard to find tailoring supplies, and I wasn't able to get everything I needed from one place. Here's the two I'm going to:
B Black and Sons
Has fabrics as well as notions and materials like hair canvas and clappers. Didn't have lambswool, though.
Bergen Tailors and Cleaners
Had the missing lambswool by the yard, as well as a lot of other supplies but didn't have clappers or good prices on ironing materials.