Plain ol' long-grain or basmati rice goes in the rice cooker at the ratio of 1 cup rice to 2.25 cups water. Jasmine/sticky/brown rices get almost 2.5 cups. Regular Chinese rice only gets 2, I think (it's been a while). Soaking the rice in water for fifteen minutes before cooking lets the water penetrate better, but you might need slightly less water. It's a good technique for brown rice, which has the external layer that impedes water penetration. Some people prefer to rinse the rice first - this washes away extra starch which causes the grains to stick together (it also throws off the liquid measurements, so you'll be forced to guesstimate and learn by experience).
For a flavor boost, heat a tablespoon of oil and toast a teaspoon of whole cumin seeds in it - add this to the rice + water before cooking. Especially nice with basmati.
You can also substitute some kind of stock for part/all of the water. Or throw in a bit of bouillon for flavor. Really, just go experiment. Rice is like blank paper ready for you to draw on.