1999 saturn four door ac stopped blowing doesnt blow cold or hot air at all. What do I need to look for?

You need to fix the coolant leak, then refill and bleed cooling system, then you will get heat and cure overheating problem too

I would make sure the shut off valve between the cold air and warm air is engaging. this is controlled by a vacume

Most likely the freon has leaked from the system. Replacing it is a fairly simple process, but finding and repairing the leak is expensive (labor wise). Plus, in the States, federal law prohibits non-licensed personnel from working with freon and it's descendants. Find a good AC service shop and get an estimate--you may not need that AC air as much as you thought! Good luck!

If the a/c is properly charged, the failure of the temperature actuator for the HVAC system would cause this symptom.

on my 99 devillle concours cold air blows from left and back vents but hot air blows from right vents

if u have a restriction in the condenser or the expansion valve thi will happen needs gauges put on ac to see which is ur problem

The actuator motor is bad and needs to be replaced for the right side.

check cooling fan operation while ac on.If fan is working proper,will probably have stuck exspantion valve.

Sounds like your temperature actuator is not moving or your temp door is broken. On max a-c ,coolant is shut off to your heater core allowing only cold air in.

No, you just need to fill freon gas.