Okay, first take a deep breath. Now that you're done calling Yuffie every name in the book, relax. She has a really good reson for what she just did to you, which is take all of your materia and leave you at the mercy of the Shin-Ra guards. Finding her and geting your Materia back will be a pain, but it's a pretty funny side-story. There are two parts to the quest: Getting you Materia back and Climbing the Pagoda
Getting Your Materia Back
Yuffie's Sub-Quest Starts the first time you land near Wutai, which is on the narrow continent at the far left of th map. You end up there after you steal the Tiny Bronco. She'll say that she need to guide you, and then take off when you are accosted by the Shin-Ra soldiers. If she's in your party at the time, you'll only have two people to fight the troopers, so you may want to take her out of your party. When you fight the guards you will have no spells.
After the fight, you realzie what's going on, and you are stuck. The game won't let you get back on the Tiny Bronco once Yuffie steals all of your materia.
Make your way to Wutai by heading north acrossthe bridges. After the second bridge, go around the moutain to find the path. The enemis here can be brutal, but they give you Phoenix Downs and X-Potions, so use them if you need them, and save often.
Wutai is on thegrassy plain. When you come into town, you will see Yuffie, and she will run away. At this point you have to track her to four hiding places:
In the Materia/Item shop open the chest. If the chest is blocked, talk to thewoman atthe counter, leave, and then come back. You will get a Materia that Yuffie will promptly steal.
In the hou