I have the same iBook.
Before anything, make sure you check the brightness (2 of the F Keys - I can't remember which ones) - just in case.
There's a known issue with the video logic board that sometimes effect external monitors as well on this model. There's a decent chance an external monitor won't work even if you can connect it. But to try, you'll need the special ADC (IIRC) adapter which will give you VGA connectivity.
Either way, You're going to have to have it sent out for repairs if you want it working again.
But the potential good news is that there's a chance it's covered under an extended warranty Apple issued for quite a few of these iBooks. There was a bad batch of them they released a few years ago (if it's in that range). I ordered 22 of them at my last job and 10 of them had to be sent back before I left the place.
I would call up Apple and ask them about it. They can help you further. Their customer support is excellent.
