The Local Currency

The following are the Coins and Notes / Bills in Chile:

Chilean Coins: $1 - $5 - $10 - $50 - $100 - $500
Chilean Notes/Bills: $1,000 - $2,000 - $5,000 - $10,000 - $20,000 - ($500*)
*There is the odd $500 note floating around but most of the time you will see the coin version.
In local Chilean slang (especially with the young people), the $100 peso coin is called 'una gamba' and the $1000 note is called 'una luca'. 
By the way, don't pay the bus drivers with anything less than a $10 coin as they will often throw them out the window while looking at you in disgust.  
You will have no problem changing US dollars into Chilean Pesos here in Chile. (Currently the exchange rate in Chile is US$1 = CH$610)