The price for now is 0,5$ per 1PPO, additionally you'll get bonuses depending on the size of your purchase.
How many tokens will be allocated for bounty?
Just visit the bounty thread and you will get more information about how much allocated for the bounty campaign https://bitcointalk.org/index.php?topic=5113105.0 it says 2% from the total token sold will be given to all of the bounty participants.
When can I find out how much 2% will be in tokens?
There are 65 000 000 PPO tokens offered for the IEO. And how much those 2% will be depends on the total PPO sold after the IEO.