airport express for ibook g4, orginally downloaded on an IMac

[shakedownstreett]

I have an ATT U-verse wireless network which I am trying to set up an Airport express to play music on a home stereo. My Ibook G4 does not show any Airport express in the Airport utility. The express is plugged in an shows a slow blinking amber light. When I load the disk into the lap top it shows that a newer version is loaded, but still can't find any version. One more thing, this express was probably loaded in an old Imac that I don't use, but did not delete any files from. any ideas?