This tutorial is so easy to do and also very cheap. All you need to success is a 6mm long tripod screw (1/4") and a bottle-cork. IMPORTANT. You need to have the exakt thread on the screw for this purpose or you will destroy your cameras thread. If you are unsure, bring your camera to the store.
I bought my screw in the hardware-store for around 0.30$. You also need a drill with a 5.5mm diameter size. 6mm might also work.