Matt and
to Aussie Pinball.
My advice with the first pin is to take your time, ask as many questions as you like and see the game "in person" - or have someone you trust look on your behalf. After you have made 20 posts, you can view the trader section where members sell their games. This is almost ALWAYS the best place to find your first machine.
Remember to ask questions before you go out on your quest. Advise is free !