There are 30 Chinpokomon dolls that you can collect in the game. There are quite a few of them that are missable since they’re located in certain areas accessible only during the main quests. After collecting all 30 Chinpokomon, the Chinpokomon Toy Corporation will be added to your friends list.
1: Chu-chu Nezumi
On a tree west of Butters' house. You have to knock it over with a ranged weapon.
2: Furry cat
Beside a tree, further to the east of where you can find Francis / Mr. Broflovski.
Tower of Peace, second floor on a cage to the right.
Butters' room, near the window.
Found in Cartman's garage
6: Shoe (Missable)
During the quest "Beat Up Clyde", this is found near the top of the tower where you have to raise the gates using the wheels on the eastern and western towers. Teleport to the topmost balcony to reach this.
Found in the newsroom. You need to enter the vent while in gnome size.
Found in the basketball court beside the Community Center. Use the alien probe on the eastern wall of the Center to teleport there.
9: Fetuswami (Missable)
During the quest “Unplanned Parenthood”, once you've reached the part where you have to go past the auto-turret, shoot the the grenade the dead soldier is handling. Once the path is cleared, enter the hole then go to the left to reach the chinpokomon.
Outside Mr. Hanky's house in the sewers
Found on top of the storage cabinet in the left side of the conference room.
Inside the Community Center's restroom, in the left most cubicle.
On a tree west of the town hall. Knock it over with a ranged weapon.
Beside the chest in the girls' headquarters. You can access this after completing “Recruit the Girls”
15: Poodlesaurus Rex (Missable)
Found in the vent past the cafeteria during the mission “Attack the School”
Inside Professor Chaos' lair inside a U-Stor-it storage shed. To access the lair, you need to get the Chaos Lair Key from Butters' room. Then, you have to hit the ladder above the dumpster beside the hobo/street merchant. Once inside, go north then east then open the right-most storage. The chinpokomon is located on top of the vent.
17: Donkeytron (Missable)
Inside an oven in the school cafeteria. You can access this at the start of the main quest “Attack the School” As soon as you enter the kitchen, turn the stove on, go to a short distance and use Cup-a-Spell to blast the oven, freeing the chinpokomon inside.
Inside the Broflovski Garage. After getting dragged to the Elven Kingdom, exit through Kyle's house and find the key inside his parents' room.
On top of the ticket booth in front of the cinema.
Found on the top shelf in Mackey's storage. You can get the key by talking to him and getting the quest “Wasted Cache”
21: Pterdaken (Missable)
After defeating the mini-boss and reaching the second floor of the school, head to the southeast hallway and open the only unlocked locker there.
You need to learn the Nagasaki magic to break down the rock leading to the drumming crab person, deep in the cavern below the town. You can reach it by fully exploring the sewers.
In front of the Tower of Peace. After learning the Dragonshout from Cartman, stand in front of the lamp, press G and release to fart. This will blast the fire off the lamp and defrost Brocorri.
On the second floor window of Token's house
On a shelf in Skeeter's Bar
26: Beetlebot (Missable)
After freeing Randy Marsh and using the White Power Crystal to activate the elevator, you'll find this on top of the monitor screens to the east, right after exiting the elevator.
Go to Stark's Pond once you have the alien probe tool. Beam yourself to the sunken UFO to find this chinpokomon.
Found in the upper shelf of the Police Station's Evidence Room
On the attic while finding another way to the Bard's room
Under the bench in front of Tweek Bros Coffee. You have to shrink yourself to reach it.