My blackberry curve's screen cracked, so I ordered a new one off ebay. It came today fitted it and the screen is white? any ideas why or what I need to do? thanks

Sounds like you got a bad screen, or perhaps you didn't get the correct version. The Bold 9000 for example has over 4 different screen versions and they are not interchangeable. There's 001/004, 002/004, 003/004, and 004/004 and you must ensure the correct version or else you won't have a proper operating screen.

You might also make sure the ribbon cables are connected correctly