Nope, cryptography != steganography. The situation with stego, currently, is much the same as the situation with crypto was before the invention of public key encryption: truly high-grade stego is only available to governments, mostly because nobody knows how to do it in a secure way. In other words, stego is an art, not a science, just like crypto was before PKE. There are no good texts as far as I'm aware.

Your best bet is to read whitepapers on stego. See https://news.ycombinator.com/item?id=6843575 for related discussion.