I'm sorry that it's a problem that brought your here, but we're glad you stopped in!
Your first priority, than not driving as car that's got next to no oil, is finding there leak... Without knowing where the leak actually starts you'll have terrible time figuring out the cause. Best case scenario would be your
oil pan gasket*, but since you've found oil on the left side of your engine I doubt that's it. Let us know what you, or the shop find out so we can help if the it happens to another member.
Welcome to NICO!
* Z's technically don't have an oil pan gasket, the FSM calls for RTV.