[25% likelihood]tune up
tune up on a 99 granprix = spark plugs and wires, oil change = $100 in parts and materials.
I list this first because it is the cheapest fix and can be done by most people.
[50% likelihood]fuel pump = $250ish plus install.
If it is your fuelpump, the reason you have to turn the engine over more than once is because you are having to prime the system because it can supply enough fuel for starting. This is common. If this is the case, your car will not run well passed about 3500rpm because the fuel pump isn't supporting it.
[25% likelihood] something else