JohnnySheffield you just need to register as a Steamworks Developer, then you get access to the SDK, i did it and i have access to them.
But i wont post them ;) you sure know why
It may be that you need a Greenlight Pass (Submission Fee payed)
But if thats the case, and you want to develop a C2 plugin, i can give you a tip.
//EDIT: Maybe Ashley will take a look and develop an official plugin, i dont know what the future holds, i only know that i will take a closer look at it this week.