the gate between the two stores or if your past that and froopy is with you go all the way to the back then go all the way left
i didn't use any you have to find the right combination of attack that does the most damage the only places to get are the lab or the guy that sells them in the alleyway or when you get the x-ray goggles and look around the map and you can find one but that's after saving midnight and talking to her