One of my BIGGEST pet peeves is open ended threads like this where the answer to the problem is never posted. There are so may issues that it could have been, that it would be helpful to unknown numbers of people searching the web for answers to similar problems. For example, question never asked was CAN the key be turned to the START position? if not there are only two places the problem can be, first is in the tumbler itself, which is very easy to remove with a pin and the key, and have a locksmith repair. The second place is in the column, to test that, take the tumbler out and insert a screw driver, and turn, does it start? if it doesn't turn, the problem is in the linkage or physical switch, both of which are mounted to the column below the dash covers. The next thing to check if the key DOES turn all the way is the starter Solenoid. simple enough with a 12 vlt trouble light or a meter ground one side of the test device and hook the other to the solenoid input and have someone turn the key to start. do you get voltage? Yes? bad solenoid . NO? check the master fuses in the engine compartment. IF the solenoid IS operating and noted by a solid CLICK but no spin, its either a bad solenoid or starter. clattering clicks power connection to solenoid or battery. It really is that simple. But don't start a thread and walk away from it and leave people who tried to help wondering. You are also leaving others looking for help high and dry.
I try to close threads like this, when I find them, so that they are useful to those in need. Even though others may cry about resurrecting an old thread. It may be old but its only useless if there is no answer posted.