That also states that there is 2 defenders infront of the receiver. When infact, one of them is the goalkeeper who does not count to this rule. If the receiver is getting the ball passed to him when he has no defenders (not including the goalkeeper, who can be anywhere it doesn't matter) goalside of him, then he is offside. If he has one defender (not incl. goalkeeper) goalside of him or the ball is being played from a position on the pitch closer to the goal than the receiver is, then he is not offside and can advance with the ball when he gets it.
Oh, yeah, and Faceman is right. Can't be offside from a throw in either. But any other set peices. It is about timing, if you are in an offside position when the ball leaves the passers foot, you are offside, it doesn't matter whether you're in an onside position when you actually gain control of the ball.