here is a complete walkthrough for the ninja bit
1. Talk to (i know the doll mans name starts with O.. so ill call him olga) olga about his porclein pirate thingo.. till he mentions the rare ninja model
2. You get the option to say something along the lines of "Look its the ninja"
3. As olga turns around.. you pick up one of the pink dolls
4. Go dump this pink doll in the tar near the news agency thing
5. Get your club 41 card from the socks on the clothes line near the ship
6. go to club 41
7. Pick up that olive sword thing
8. Combine tar doll and sword
9. Follow the map (which you also get from olga by talking to him about how he got scammed)
10. Put the doll in the hole 