Ouch. This could be a number of things such as a faulty cable, faulty card, or an issue with the screen itself. I'm afraid that the diagnostic and repair could get pricey, and might cost you more than a new laptop.
In my own experience, I usually don't salvage laptops in the case of a hardware failure (unless it's RAM, a HDD, or a simple ribbon replacement). An LCD replacement in itself can run 100-200 bucks.