Whoops. Posted to the wrong person. Not enough coffee.
Try again...
The question mark is a sign of not having a 'blessed' system folder.
I'd boot from the system disk, run disk first aid, at least, and try again.
If you have any higher grade disk repair software (tech tool, norton, disk warrior), I'd give them a shot first.
Following that, if the G3 has never had OSX on it, I'd check re: firmware updates, minimum version of OS9 needed, etc.
Good luck.
And ignore the heathens.
ROFLMAO! So far, this is the best advice, right up there with buy a new Mac. Not sure what all you use your Mac for, but the G4 iBooks are great and pretty affordable. Do you have an Apple store near by? Take it to the "Genius" and they can help you.
Cheers, CC :)