From YouTube - ADM3 Transformer Rewind Part3 by Jerry Walker on good books for transformer and inductor design:
There are many to choose from. I have quite a few but two I originally referred to most were: TRANSFORMER AND INDUCTOR DESIGN HANDBOOK Third Edition, Revised and Expanded COLONEL WM. T. MCLYMAN This covers the actual transformer design And: COIL WIND1NC GEO. STEVENS MFG. CO .. INC. Which covers the actual winding process.