Welcome to MacNN.
1. Don't put "Help PLEASE!!!" and the like in thread titles -- it's just noise.
2. Post in the right place. Technical questions belong in the technical forums. This is a question about a peripheral -- we have a whole Peripherals forum.
3. "Mac G3" is too vague a description. There's no one model by that name. As for whether the KB will work: If it's a Power Mac G3 or a very early PowerBook G3, then yes. If it's a later PowerBook G3, or an iMac or iBook, then no.
tooki