If you haven't collected all of the goodies from the parking lot where the battle with the final survivor took place, be sure to do so before heading into the next area. Grab the lollipop off of the hood of the car to the middle left of the level, and head to the back right-hand corner behind the bus to find a collection of coins for you to collect. Once you've snagged all of this stuff, proceed to the next area via the alley by the large arrow and the survivor.
As you shepherd the last survivor onto the helicopter, it will be downed for good by a pack of hungry zombies. With a promise to "meet you in the square," the pilot will go down with the ship, so to speak. Juliet will receive a phone call (her phone is conveniently attached to her chainsaw) and she'll speak briefly to her mother. Over the course of the game, you will sometimes see a phone icon pop up on the side of the screen. The game never really makes this too clear, but there is no button that you can press when the icon appears to hear the phone message right away. Instead, you will have to pause the game, go into Juliet's stash, and listen to them one by one there. It's kind of an odd way to do the whole "message" thing, but it's the only way to do it in the game.
Once the phone call is complete, head up and to the left to find a stash of coins and a lollipop. Grab them and tun to the right to find a shop. Press the X or A button at the storefront to enter the shop. Here you can buy not only extra lollipops and other items, but also new combos, clothes, and even character upgrades. You can upgrade Juliet's health, homing attack properties, recovery speed, and more. As Lollipop Chainsaw is a relatively short game full of collectibles, you will probably end up wanting to play through it again. It will make your first and subsequent playthroughs easier if you focus on upgrading Juliet's health and strength first and foremost. You can purchase extra combos and clothes in another playthrough, or towards the end of your current one. Make your shopping choices and exit the shop.
Kick down the door to the right of the shop and run down the alley behind it. Seven zombies will run down the fire escape at the left-hand end of the alley. Use the thin alley to funnel them all towards you and cut them down with your chainsaw. Be careful of the named zombie who will be among the smaller ones. This zombie will have vastly more health, in addition to stronger melee attacks. Dodge behind the named zombie when it attacks, and hit it from behind. Once the named zombie has been dealt with, the rest of the fodder should be, well, fodder. Easy pickings.
Follow the alley as it curves around to the right. Turn to the right and loop behind the chain link fence to grab a bunch of coins and an extra lollipop. When you are done with everything here, head to the ledge to the left and hit the Circle or B button to jump down to the next area.