iPhone App Store Distribution questions

Question

I would like to enroll my company in to the iPhone Developer Program for $99. I have a few questions, which I can't really find an answer to, because Apple aren't very detailed in their pages unless you actually registered.

So here goes:
1.) Is the $99 paid yearly?
2.) It says when distributing free apps there's no fee, but if I want to distribute a $0.99 app, what is the fee then? Is it huge? Or..?
3.) Can I keep track of how many people bought my app anytime?
4.) Is there a page on the internet where I can read more about app store distribution that explains almost all the info I need to know? (Apple doesn't satisfy me on this)

Thanks

Answer 1

1. Yes
2. Apple take 30% (You still have to pay the $99 even if your app is free)
3. Yes
4. I've found that apples developer centre is pretty good and explains most of this information, it is maybe not the easiest to navigate though.