I had to learn what my partner likes but it wasn't really hard haha, I love doing it (as long as I'm in the mood for it), I don't enjoy receiving as much since I'm transsexual, it's quite uh... dysphoric. Very nice, and I trust him VERY much, but I'm so ashamed by my parts that it's hard to fully enjoy it. I can't really get the idea out of my head that I can fit him fully in my mouth (well, when deepthroating), but he'll never be able to do that to ME, only what's on the outside, and stimulation inside really makes it good. Finger play and toys help, but it's not the same. Plain ol sex just feels better for me. Again, I have a hard time enjoying it because of dysphoria, no matter how good he is. No book is going to help that.
But anyways, yeah I don't really understand books like this, unless you don't know -any- anatomy and aren't sure where nerves are and such... I don't know.