When you say it's failed, exactly how has it failed? As Richard suggests, check you haven't accidently switched the graphics output away from the screen.
If that's not the case then it could be either the imaging system &/or the backlight system. If you look closely while shining a bright light at the screen can you see a faint image? If so then it's the backlighting that's stuffed.
This is commonly due to one of two things: the inverter that converts battery DC voltage to AC, or the cathode ray tube itself.
Typically inverter boards are easy & relatively cheap to replace. Just be careful about residual voltages etc. The backlight itself can be more of a problem. There are quite a few places that sell backlights but you'll have to disassemble the screen to find out what's needed.
Therein lies the bugger. Not all backlights are easily removed from the screen. If that's all OK then the new light will likely need some soldering to connect it. The lights are very fragile so be gentle! Some places not only sell the lights but offer a fitting service as well.
If it's the imaging system then you're in more trouble. If you're lucky - and it's the graphics chip that's stuffed - then it might be possible to unplug the graphics chip & insert a replacement. Many laptops, however, don't use socketed graphics chips, using surface mounted chips instead. If you're good with a soldering iron & have the necessary heat sinks then replacing the failed chip might still be an option.
Otherwise if it's the LCD part of the screen you're pretty well stuffed. Ebay have many screens for sale. You will probably find a suitable replacement to fit your laptop, possibly even cheaply...
One last possibility: One of the wires might be shorting/open circuit between the chassis & the screen. Those wires get a lot of bending & moving in their lifetime.
Good luck!