do you have a schematic already of the circuit your building? I repair concert lighting equipment that uses discharge lamps. I can tell you, the transformer is a ballast and the high voltage igniter circuit basically momentarily pulse shorts the ballast transformer to cause a high voltage spark across the lamp. once the lamp fires, the ballast limits the current to the designed current. This operates much the same as a florescent lamp only much higher currents. The 2nd option is to use an electronic ballast type that the power supply regulates the voltage and current to match the lamp. THe igiter is an external high voltage "kicker" device.
which type are you trying to build so we can help further?
-eric