Where is the lower connection on the 97 grand am se AC repair connector located

are you looking for the low pressure connection? it should be on the reciever/dryer. If you are not familiar with an a/c system you really shouldn't mess with it. if your system is drained of freon good chances are you have a leak. if you charge it without fixing the leak ,you're just wasting your money. also before you charge it the system it must be put on vacuum for about 15 minutes to evacuate any moisture & to see if there are any leaks. also too much freon can/will damage the system.