You want someone to hand you this guy's cloaking method on a plate so you can copy him?
It's best to figure it out yourself so you will learn something.
IP,UA,Referer cloaking is so 2003. Think outside the box and use a cloaking method that doesn't rely on http variables, uses a flaw in all algorithm based engines and therefore won't be patched/detected until a next generation SE comes out.