My 2008 Chevy Impala is leaking a lot of oil around the front passenger side tire..2 wks ago I was trying to figure out why it wouldn't start.. then remembered my car note was due.. call the dealers

It could be oil, could be transmission fluid, brake fluid, What color is it?

The oil could be coming from a lose oil filter. If you can have someone run a paper towel around the filter and see if it is coated with oil, that may be the problem. Start on top and work down wirth the paper towel to see where the oil leak starts. Remember gravity causes the oil to run down, and since it is in the front of the engine/car, and on the left side, that is where you should concentrate from the top down. Check the valve covers which is a common leakage problem. Next go to the area between the heads in the "valley" between the heads as a valve cover gasket may leak there and the oil runs out in the front. Check around the timing chain cover. Don't forget the filter. Check last the oil pan for leaks, and the drain plug. that is the quick go round for checking. If you can see the trail the oil is making as it leaves your engine, that is a great clue where the leak is coming form. Let us know what you find. It may be a cheap fix. Removing the valve covers and putting on a new gasket may run close to two bills but it really shouldn't. Why did "they, who ever they were" tell you to shut off your engine? Did they have any idea about the oil leakage and where it came from or the cause? Let us know.