Playing music wirelessly from laptop from itunes with wifi?

ok, heres my setup: i have an asus vista laptop with wifi and bluetooth , a g3 emac plugged into the router also an g5 imac also with wifi and bluetooth which has jbl speakers plugged into it. i am running them off a wireless router. and so i am wondering if there is a way to play songs from itunes from the laptop through the speakers wirelessly either through bluetooth of wifi. if you want to know anything lse to help me, please ask me. any answers will be appriciated.