Apple Ipad Charger Adapter for GM/Silverado 12V?

For the Apple Mini / 16GB / 32 GB series IPad. What do I need? What's out there?

What year silverado? Pretty much any of them in the last 6-7 years have USB ports in them that work (I've had a 2010 and a 2011, and have family with 2013 and 2015, all of them have USB ports that work with the Apple products).
Otherwise, you should be able to get a 12v plug with a 5v/2a USB output for like $3.