Hi There looks like one of two problems.
Either the screen has gone or the Motherboard. If you can link your Mac to another screen with a VGA cable.. this will determine if the MB is ok and the screen is defunct. Try putting pressure on the bottom left hand side of the powerbook near the trackpad when you boot up.. hold till the screen appears and see if anything happens when you let go.. this is a pressure fault VERY common on older iBooks and it is a faulty logic board. I doubt it might be the HD.. but use a firewire cable to link to another mac re-boot the iBook holding the "T" key and the HD will load on the other Macs descktop.. this way you will get you files back and know the HD is ok.