Player bonuses are bonuses that you can buy with real money to give you a boost in the game.
Go to your "Menu"
Click on "Store"
Click on "Player Bonuses"
You need to make sure that you have a credit card or have a parent or other family member with a credit card first. You go to the Player Bonuses page and find the bonus that you wish to buy, click on the "Buy from Share-it" button, and then fill out the required information and submit. You should then get the bonus shortly afterwards and an email.