I don't know about iMac G5... it may already have Wifi adaptor..
1. Get a Wireless adaptor for your Imac G5 (make sure that it doesn't have it yet)
2. get a router, connect your DSL modem and your Airport express and your Imac G5 to the router..
I have an Airport Express hooked up to my DSL modem to provide wireless internet to my Powerbook. I also have a new Power Mac G5 without any internet connection. What do I need to do to create a wired connection between my Airport Express and my G5 in order to share my DSL connection. I understand that Airport Extreme Base Stations have a LAN port to solve this problem, and I was wondering if I need an ethernet hub. If so can you tell me a simple cheap option, and how to do so.

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