Now i want to replace the bad drive,contacted mac and they said the computer is obsolete and tehy don't sale replacement pasts for this one, any idea where i may find it?Thanks again
The best place to obtain one would be eBay. Just make sure you get the correct drive for your model.
Depending on which country you live, there are some parts companies in the US/UK that I know of which supply refurbished drives for PowerBooks. They wont be as cheap in some instances as eBay, but guaranteed to be work at least.
If you need instructions on fitting a drive to your PowerBook, try going to ifixit.com or web search ifixit powerbook G4
Best of luck