Well, you are wrong, in a sense. The alternator indirectly CAN cause your car not to start. Take that plug on it & disconnect it just slightly. Like as if it vibrated loose. Then try to start your car. It will click just as if the starter is bad( you get the clinnk, clink of the starter engaging probably 10 or so times. I know I did), but once it builds enough resistance it will attempt to start & then eventually start after about 5ish minutes. But the charging system will be crap & it will drain your battery quickly.
Most people replace their alt's just because of that. ( I have talked with 10-12 people on AIM that have had this problem).
SO IF the connectios on the ALT are loose. It CAN cause a no start.


As for what else was said. Check your gounds. Also the wining fo rthe starter might be loose. Go over all teh charging & starting connections. Make sure they are tight.

If it is the starter, it is quite easy to take out with the right wrenches. You dont even need to jack up the car.