Where is a good tutorial for starting pron style 3D renders? I'm doing OK with positioning models, but the good manipulations (like genitalia or boob grabs) are a bit difficult. I'm OK buying morphs if that's whats needed
I don't think there's a single tutorial for CGI porn, to be honest. And, yeah, morphs (and, in modern DAZ terms geocraft genitalia) are essential, but, what also is even more critical, is to pay attention to the little details that are not always (sometimes not at all) available as morph packs. Like a throat bulge during a deepthroat scene, or a stomach bulge for deep penetration, for example.
Luckily for you, there are several helpful bodypart and genitalia geocrafts you can grab, that can be set for collissions, like the breastacular breasts, the golden palace pussy, and the fender bender buttocks, saving you the painful, lengthly manual morphing in hexagon, blender, or whatnot.
BUT... the most important things, that no tutorial will ever manage to teach, is having a vast enough imagination, to create intriguing scenarios, and attention to detail, to carefully look for, spot, and fix tiny little details, that can easily turn something from "whoa, that's epic" to "meh, it's ok, I guess" level of quality.
My honest advice? Keep doing what you enjoy, for as long, and as much, as you enjoy doing it, take small breaks when needed, to clear your mind, before you get burned down, and... practice. A LOT. Think of something like "post one render out of every five you make" while you don't have anything specific to work on, so that you have 4 renders to experiment, and learn as you do