My husband and brother-in-law both have this problem. Be sure you are not over-washing your hair, stripping it of natural oils, as your glands will work harder to restore the oil. Use a mild shampoo. No time to wash in the morning? Use a great dry shampoo; Ojon and Oscar Blandi both makes versions which would work well with short, thick hair, leaving no residue behind.

Baby powder, dry shampoo.

I agree that over-washing can cause greasiness at your scalp. So best to use mild and organic sulphate free shampoos and conditioners. However, all oiliness is not caused by that. If your hair is dry even then the scalp gets oily. My hair stylist once told me the best solution to an oily scalp for people with dry roots and/or hair is oiling it regulary before washing. No matter how absurd that sounds it really works. On the other hand if your oiliness is caused by product build up than you need to use a cleanser once in two weeks to get the build up out of your scalp. I know aveda scalp benefit balancing shampoo and Neutrogena Anti-Residue Shampoo are for this purpose. You could check out more. Also for the second type of oiliness dont use conditioner and leave-in conditioner on your scalp area. Hope this helps.