Separate names with a comma.
The SDK is free to download but the $99 is to sign up for the portal so you can test on an actual device and release free or paid apps on the App...
You'll be lucky to get away paying with a promo code, people generally would charge a lot more. Also, I think the codes can only be used in the US.
Another recommendation for Hillegass's book. You don't need anything else but that, in honesty.
