Now that you have the Prism in your possession, four buildings will come into view around Dezo. Just as the Dezo wilderness is divided into four regions (three of which have towns), one building occupies each region. They have varying degrees of difficulty and complexity, so you should start with the easiest one: Menobe. Menobe is also very easy to reach. It's just a short walk west from Aukba.
Menobe is another labyrinth of a building, with four floors that are effective broken up into two wings. There are also four treasure chests to find, all of which are some kind of head gear, and two of which contain pieces of Nei equipment. You'll need to climb and descend multiple flights of steps to collect items, so rather than providing a walkthrough per floor, the means to obtain each item is presented below the maps.
From the entrance on the first floor, walk up until you are inside the central section with three staircases. Climb the left staircase. On the second floor, walk down and follow the path on the right that hugs the middle of the building as it travels all to the bottom of the floor. Then head to the left, following the outside edge as it begins to curve upward. A chest will be at the end of this path. In it, you will find the second Storm Gear in the game. It's very likely that if you made use of the first one, you gave it to an underpowered fighter like Amy to do much more damage to every enemy than she could do otherwise. This is a chance to give the item to another such fighter, if you so choose.
Neimet - 3rd Floor
The Neimet will take a lot of wandering to find. From the entrance, walk up until the middle before following the left path around the central tower, and head to the upper left corner of the building. A whole in the wall will allow you to walk down and follow a path that curves to the right. You'll see one staircase, but pass it and continue on until you reach the second set of stairs above it. Climb to the second floor, and head to the left. You'll see one upward staircase come into view, but don't climb it. Instead walk straight up to find another flight of stairs to the third floor. Climb up that one, and walk up. You need to follow the outer edge of the building to the right, until you reach the upper right corner. Then head down and in through a hole in the wall. Follow the path back up to steps that go up. Climb to the fourth floor, and take a step down. The path splits here, so follow the path to the right. This should take you down, and all the way around the edge of the inner part of the wing, leading you up and around from the right wing back to the left wing. When you see a chance to slip in to the left between some columns, do so and continue down until you see a flight of steps leading down. Take them and you'll arrive in a sectioned off room on the third floor where you can collect the Neimet, which offers incredible head defense for Rolf.
Color Scarf - 3rd Floor, and Nei Crown - 1st Floor.
From the entrance, walk up the center path, step into the tower, and take the right set of stairs to the second floor. Walk down, following the edge along the center. Ignore the first set of stairs down that you come to, and head to the right until you find a hole in the wall that you can travel up through. Take the stairs up to the third floor that you find there. You will arrive just to the right of one chest which contains the Color Scarf. The Color Scarf is one of the better pieces of head equipment that you can give to Anna. It also casts Saner which increases every party member's agility. Continuing on, walk up through the hole in the wall and then to the right to find another set of stairs leading up to the fourth floor. Up on the fourth floor, you need to move left, up, and back to the right to find a set of stairs leading back down. Back on the third floor, head down and slightly left to find stairs leading down to the second floor. Walk up and slip through the narrow gap to reach the next flight of stairs down to the first floor. It will deposit you in a sectioned off room with a chest that contains the Nei Crown, the very best head equipment that Amy can make use of, so be sure to give it to her.
