Remove the starter motor and inspect the teeth on the ring gear and the starter drive gear. If they are okay, either the starter drive's over-running clutch is bad or the flex plate is broken around the center where it bolts to the crankshaft.
You can also try turning the engine a little by hand, then try starting it. If that works, suspect worn ring gear teeth.
March, 9, 2012 AT 8:22 PM
The starter and fly wheel are good. Could it possibly be a bad alternator?
March, 9, 2012 AT 8:42 PM
The generator has nothing to do with starting the engine unless the battery is discharged.