Photo emulsion is pretty easy. Print off on a transparency or do a cut out of black paper and in a dark room: coat your screen, let it dry, get a light bulb that emits "natural light", let it expose for such and such time, and then rinse with water. When you're done, you put photo emulsion remover on it, let it sit for 15 min, then rinse it off with water. I haven't done ruby-lith, but it's definitely easier than using red blockout or blue drawing fluid. Stencils from contact paper are less complicated, but they take about as much time and they don't get very detailed.
And all the silk screening inks I have used have been acrylic. I know you can get oil based, but I think that's a bit silly, due to all the solvents you'd need to clean out your screens.