Our concern is to design some deterministic schemes for remotely preparing an arbitrary W-class state from one sender to one of a number of receivers. Compared with previous remote preparation schemes, the real receiver in our schemes is unknown to the sender. Firstly, by introducing a novel entanglement transformation the sender can deterministically prepare an arbitrary W-class state with complex spectra to one of two remote receivers via two four-particle GHZ states as the quantum channel. As for preparing a W-class state with real spectra, by constructing a general and useful measurement basis for the sender, another economical protocol can be designed with unit success probability. These schemes are extended to multiparties via two multi-particle GHZ states as the quantum channel. The classical communication costs of all the schemes are calculated to determine the classical resources required.