Q: How do I fill out the W-8BEN form as an Australian?

Hello.

I've searched around and have so far not found anything conclusive as to how I fill out the W-8BEN form required by iTunes Connect. I need to fill out these forms to sell my apps. This will be my first app, and I'm only 18 so I've never filled out W-8BEN's. Particularly, what do I put into the U.S. taxpayer identifier number, Foreign tax identifying number, and Reference number fields.

Also, lines 9 and 10 is a bit confusing. I guess I'm supposed to check the box on line 9 (Which says I certify that the beneficial owner is a resident of Australia within the meaning of the income tax treaty between United States and that country). I have no idea what to put in the boxes for line 10.

Please help me, thank you.

P.S. Reminder that I am Australian.