The reason why it's so much easier to stir-fry in a wok than a frying pan is because the wok has sloping sides. As your stir and toss the food, it goes back down the sides to the centre where it's hottest, only to be tossed up again, whereas in a frying pan it just spreads around the base of the pan (or the kitchen, in my case). I don't really know anything about ceramic hobs, but could you use the same kind of ring that that round-based woks stand on on electric hobs. Would a flat-based wok work? They are available in a range of materials. By the way, non-stick woks can't be heated to the high temperatures required for stir-frying.