trying to connect my i-mac with powerbookG4

Hi, I have an I-mac at home and have just got a powerbook G4 laptop. What I need is to set up my Home computer as a base station so I can use my G4 around the house, but as I am a relative newbie I have no idea how to go about this ( probably very simple ) task. I would be very grateful for any advice.Tried airport utility, it scanned but did not find device. but the triangular airport symbol is not showing any bars on my i-mac. Willie.

what you are trying to do is called an ad hoc network. this link should help, the wi-fi portion is towards the bottom of the screen.
Ad hoc networking | Utilities - Page 1 | Macworld
if you could let us know how it went or if you encountered any trouble please post again

best of luck