How do you know if your lcd is going out?

hi there, i've been experiencing this annoying problem with my late 2008 unibody macbook, the screen freezes, turns white and pixilates away. i usually have to mess with it to get it to stop, like wiggle it and move it around. but lately its gotten a lot worse and wiggling it simply isn't going to fix the problem. i don't know what to do and don't have any to hardly any money. this computer means an awful lot to me and everything else works great, but this problem with the screen is getting out of hand. do you think its my LCD or perhaps something else internal is causing it? would this be an easy fix for myself to repair? how much do you think a specialist would cost?

thanks, i totally appreciate any help!