Did it just die, or did it stumble and run poorly before it stalled?

Did the MIL light up?

A repeated sudden die-out is usually the igniter.

Just making we're on the same page: with not turning over, you mean "not
cranking" or do you mean "cranking but not actually catching and starting"?

If the car is not cranking at all,  it may be your starter or something
related to the starter.
Do you hear a 'click' under the hood when you turn the key?
If you don't, measure the voltage between the fat wire to the starter and
ground (be careful to not short anything, because that is capable of
delivering a lot of current). No need to start the car -- just measure the
voltage.
If you see 12V or hear that 'click', put a piece of wood on the starter
(like a 2x4) and whack the piece of wood with a hammer -- not too hard, but
hard enough to mechanically shock the starter.
If the car now starts while hitting the wood, chances are your starter is
bad. Check and clean all connections first, though.

If you don't see 12V on that fat wire, follow it back to the battery. Clean
both ends and inspect the crimps.
If you do see 12V on the fat wire but don't hear the click, check the
voltage on the smaller wire on the starter. Start the car. If you don't see
12V there, there's a chance that your ignition switch is bad or the wires to
the ignition switch are bad somewhere.

Before we go too far diagnosing, let us know what the car is doing.
Remco