Implied Volatility

So, where is a good site to get the IV for particular options?

 

Ivolatility.com is free and gives you some historic IV charting too.

 

http://www.ivolatility.com/options.j?ticker=amd&R=0&top_lookup__is__sent=1

Why does it give two different values for the IV? One on the left column, and another on the right column.

What about the December options?

 

One is the call IV and the other is the put IV.