Phat_Pat said:
Airport Express is also a G. Just doesnt have any physical ports to plug your mac into.
Hmmm... tell that to my old iMac which is now plugged into my AirPort Express via ethernet cable, using it as a bridge.
Oh, and just to be clear (well, I think it was clear already, but just in case): there is no charge whatsoever for using a wireless network device - as long as its connecting to your own network. In that case, it's just replacing ethernet cabling with radio-based connections.
If, say, you go to Starbucks, you can pay for using their wireless network, which you access via your AirPort card. Many places offer wireless access for free, and some places charge for it. Rates vary.