What do I need to travel outside the country?

I currently live in U.S., Georgia & I am planning a trip to Australia at the end of the year. I know I need a passport & I already know where I can get one. I know you can apply for a 3 month visa online, which I plan to do. & I need to get my license & a credit card (I'll be 18 in July). But, what about buying tickets? What's the best way to purchase plane tickets? I know I can buy them online with a credit card, but can you even have over $2000 on a credit card? & what else would I need to have to travel? Please help, I really want to take this trip.

If you are going to buy tickets online, call your credit card company to check your credit limit. Good luck.

Even if you don't have enough credit, but you've got pretty good credit history and all, you could request for a higher credit limit, that's what I did, just call into your credit card company and request it =] but since you're 18...i'm not sure. It's a little skeptical, but try!