How to wire a single pole switch/outlet unit...?

Well its impossible to see the markings on that device, so I'm basing this solely on what I can see in the photo. You should have two sets of wires coming into your box where the old double outlet was. One black/white/green from the fan, one black/white/green from the breaker box. The wire coming from the breaker box is your hot source. Connect Both green wires together on the ground lug on the new combo device via pigtail. Hook the source black to the dark screw on the one side (Left in the photo) next to the receptacle, with a jumper going from that screw to the darker screw on the other side next to the switch, and connect the black wire from the fan lead to the other dark screw on the left side next to the switch. Take your power source white and connect it together with the white wire from the fan, and connect to the Upper screw on the right side next to the receptacle. This should work if the switch is designed the way I think it is. What should happen is that your supplying both source leads to the receptacle which is desired so its always hot. The hot lead (black) to the fan should not get power unless the switch is on which will complete the circuit. The white is simply tapping the ground side and is always connected irregardless of the switch position.