'86 Olds Cutlass Supreme wont start

My 1986 Oldsmobile Cutlass Supreme won't start... at all. I have replaced the battery and the alternator already and its is dead, so much so that my little alarm light for my alarm system wont even light up, and its just a simple LED. I am out of ideas, and am very frustrated with the fact that my car withonly 66k miles on it in very good condition, with a good system in it wont start... (i disconnected the system, so that isnt doing anything to hurt the car) plz help i have no clue what to do and this is my last option b4 taking it in to the dealership and paying a shitload of money that i wouldnt have to if someone knows what the problem is... please help.

what could be wrong is your starter or the cable running to your starter. thats what happened to my 85 cutlass with 78xxx miles. do u know where the starter is? mine was missing one of the main blots and the other one was loose so it wasn't gettting a good ground. thus making the power cut out and not letting it start some times. if the starter is fine, check the main thick wire running to the starter. one time, thats was loose on my car and my car wouldnt start