I Fitted HID's to my headlights within the last week, got them from a crowd in Adelaide. $80 for a set to suit a commodore. Best thing is an Aussie warranty.
Power feed direct from the battery. Earth straight to the battery.
My kit took the switch from one of the headlight plugs, plugged straight in.
As a precaution I also fitted a 30A rocker switch, near the battery so I could turn off the power feed to the lights.
Brock has done a wiring diagram for the side stand to be the switch. It being Chrisie I haven't done that yet.
The lights take 20 seconds to fire up to full brightness, after that brilliant.
The globes I got were 6000k, bright white.