Most countries are able to enter Bali free of charge for 29 night and 30 days. This course falls in that time frame so you will be covered.
However, if you plan on staying any longer you need to purchase an ON ARRIVAL VISA upon arrival (at the cost of around 30$usd cash) which will allow you to extend your visa for an additional 30 days.
There are many visa agencies that can help this process once you are here. The cost is around $80usd. You are also able to arrange a 60 days Visa before you travel through an Indonesia embassy. Look on line to find the one closest to you, and also to check if your country has any other restrictions.