I followed Suvi’s instructions on how to get iButton working on the UNO.
The iButton had two wires, a white and a brown one. I connected the iButton on the breadboard. I connected the white wire to slot 7 on the UNO and to the 5v through a resistor. I connected the brown wire to ground.
After the wires were in place I went to http://arduino.cc/playground/Learning/OneWire to get the library as Suvi had instructed. Once the OneWire is extracted copy it to the folder arduino-1.0\libraries
Suvi’s code. There is also a video of the iButton in action.