[Seiryu]

This is a list containing the locations for all of the cousins and presents in the game (excluding DLC). They are listed in the order that they would be shown when you select the level, left to right, which just happens to be the order you will most likely encounter them in the level so know that if you do not find them in the order listed here you probably missed something. Also note that cousins will always appear in a level each time you play it even after you have gotten them, but the presents go away once you pick them up the first time. Another thing to note is that you must finish the level in order to receive any cousins or presents that you roll up, if you fail a stage then you will need to get anything you had over again.
With all that said, on with the list. Credit for most of this information goes to The Pants Party at (a site that is apparently blocked by the censor).

Update: List now 100% complete!

Egg School (Tutorial)
Cousin Marcy - She is on one of the rolling balls, can't miss her.

Present #1 - Same as Marcy, you are forced to get it.

Delightful Dirigible
Cousin Huey - In a corner of the room there is a ramp with a ruler on top of it. He's at the end of the ruler.

Present #1 - On the highest section in the middle of the candy shop.

Oasis Café
Cousin Kunihiro - Go on the table inside the shop, then across the bridge to the next section. He should be rolling a ball around this area. He moves, so you'll have to run into him.
Cousin Johnson - Outside in the grassy area on a striped blanket.

Present #1 - Go on the table in the middle of the shop, then up a large wooden plank into a shelf/alcove.
Present #2 - On top of a brown box in the very back of the outside section, past the fireworks/ponds.

Lady Luck Casino
Cousin Twinkle - Restart until you spawn in front of a ramp made of cards. Go up this ramp and he's at the end. If you come here when you're larger, you'll just roll up the cards.
Cousin Paula - Near the pond outside.

Present #1 - In the middle of the room, go up the stairs made of bundles of money and across a large pole surrounded by wine bottles.
Present #2 - Hidden inside a flowerbed in the garden area by the horses.

Sunrise Castle
Cousin Odeon - Restart the level until you start on the high shelf with the glass jars on your left. Roll straight ahead and you run into this one.
Cousin Fujio - Once outside, roll straight through the grassy area. There is a pyramid of cinder blocks there and he is in the middle of it.
Cousin Ryu - Hanging upside down from the white bridge over the river. You need to be about 1.2m to reach him.

Present #1 - In the top section of the candy store, go up to the right where the sink is. It is on the handle of a frying pan.
Present #2 - After going out into the city section and getting a little larger, come back to the beginning section with the fireworks/pond and it is on a red counter.
Present #3 - Outside by the brown house with the guys in black running around it.

Cloud 9 Forest
Cousin Ichigo - Running around the path in the garden area.
Cousin Pu - In the middle of the lake, standing on the #3 spot of a podium.
Cousin Kinoko - Between the golf course and where all the zebras are. If you're hitting zebras, you'll probably snag her as well since you're huge at this point.

Present #1 - A fairy is pushing this around the garden area, you'll have to track her down.
Present #2 - In the fenced in area full of livestock shortly after you leave the garden area.
Present #3 - In the city streets section, go down the alley behind the first set of stands you come to. You need to be huge to roll this one up, so you might have to come back to it.

Roller Roaster
Cousin Miso - Inside the store at the beginning, close to the door to outside, against the back wall under a window.
Cousin Lalala - Outside and across the river, there will be a tiger on a flying carpet when you're close. There should be two bridges connecting an island and she is on top of some stacked items.

Present #1 - On the table with the spinning food, up the griddle ramp.
Present #2 - This one is across the river right in the middle of the street. Very hard to miss.

Seadome
Cousin Beyond - On a street corner before and to the left of the 3m barrier.
Cousin Marny - Rolling a Katamari around the city streets area.
Cousin Mu - Out by the airport in the middle of a lake.

Present #1 - Floating down the river right in the beginning section.
Present #2 - On a boat in the water out from the big top circus.
Present #3 - In a fishing net in the water out from the power plant.

Shani Circuit
Cousin Ban-Ban - In the beginning water area with all the inner tubes, behind the island.
Cousin Nickel - In the city streets, rolling a ball of cars around.

Present #1 - Hanging from a balloon above the green grated arch. Need to be about 3m for this one.
Present #2 - On the railroad track in the first city area there is a blue flatbed train, 3 trains long. It is on the third one.

Coolhouse
Cousin June - Inside the fish tank in the middle of the house.
Cousin Sherman - Outside near one of the small pools, he is a snowman.

Present #1 - In the stream behind the little white bridge, mixed in with a pile of normal boxes.
Present #2 - Once you get 1.5m, the room inside the house opens with a big present inside.

Dynaville
Cousin Shikao - On a lily pad near the spinning man in the water by the sailboats.
Cousin Signolo - In the city streets area, usually by a line of cars. I think this one moves though.
Cousin Peso - On a plane at the airport. It's not always there, so you might have to wait.
Cousin Nai-Nai - Sitting on a boat (looks like the Titanic) that is floating on an angle in the air. Gonna be about 250m when you get this one.
Cousin Odeko - On a green island with red petals around it.

Present #1 - On top of a building in the beginning area. There is a ramp that leads up to the top.
Present #2 - On the back of Santa's sleigh, flying around the town area.
Present #3 - Behind the flag building with the elephant wearing a crown on top, next to the amusement park.
Present #4 - On a volcano when you're picking up the smaller land areas.

Schloss Kosmos
Cousin Lucha - At the waterfall that makes the river, he is on a ledge fighting a kangaroo.
Cousin Kenta - In the first city area by all the camper trailers, on the wooden bridge.
Cousin Havana - On a wooden horse by the amusement park area.
Cousin Macho - Inside the football stadium near the Mayan temple.
Cousin Nik - After hitting 300m, check the paths through the rainbows, he is lying on an island on one of these paths.
Cousin Mag - Just before you go into space, huge on a continent.
Cousin Ace - Flying around in space.

Present #1 - On a pink bird's head in the first section. He flies away so use dash to grab it.
Present #2 - On top of the snowy peak by the airport.
Present #3 - By Russia on an island with dinosaurs.
Present #4 - Inside one of the white mountains that pull apart when you come close.
Present #5 - Floating out in space.

Chatéau Notre Desir
Cousin Velvet - Under the fireplace. Get this one right away.
Cousin Norn - In the pool in front of the fountain, in the garden area.
Cousin Jungle - After leaving the garden, go left and there is a boy swinging around a tree. Underneath the boy.
Cousin Nutsuo - In the city area in the middle of all the buildings inside the sewer/river area.
Cousin Kuro - In front of the Buddha statue next to the snowy peaks/airport.
Cousin Daisy - After you pass the 60m barrier, behind the other Buddha statue.
Cousin Foomin - On the island with the skyscraper on it. (~1.5km)
Cousin Slip - Standing on Japan when you're rolling up cities.
Cousin Dipp - Floating around in space.

Present #1 - On top of a ship in a bottle by the window where the robber is looking in.
Present #2 - On the back of guy in a sleeping bag in the first water area with all the lily pads.
Present #3 - In the grassy section behind the wooden bridge where the elephants are, near the city streets.
Present #4 - Huge present near the powerplant.
Present #5 - At about 2.3km I rolled up the large floating metropolis and got this.
Present #6 - Sitting on Europe when you're rolling up cities.
Present #7 - In the middle of the black hole.

[MeatWad555]

thanks i'll start lookin for them soon.

[LilCBauer]

thanks for the compilation

A point I found helpful is you can obtain these during timed mode. I find this helpful as that way you don't have to worry about meeting the requirement of the time restriction during normal mode. Good luck!

EDIT: Well, I guess that doesn't work in all cases, because sometimes you start out too big in timed mode to get some of the cousins..

[Starz 007]

Thanks a lot man! This should prove quite useful.

[Legendary Badass]

Thanks very much, but now I'm going to be board trying to get the 100 or possibly 200 requests.

[TheBigBB]

Many thanks for this list. I would be lost without your help. With your help, most of the achievements are pretty simple!

[truejb11]

yeah thx alot this helped me sooo much keep up the good work

[Easter Bunny 00]

how long did it take you to do this!!!!!!!! amazing. thanks bro

[theghost741]

Just wanted to say that the present that you rolled up at Metropolis at 2.3K, I got at around 700m. So, yeh.

[slackgeek]

Originally Posted by Seiryu

Shani Circuit
Present #1 - Hanging from a balloon above the green grated arch. Need to be about 3m for this one.

I'm not sure if maybe this one moves around, but I found it inside a wheel barrow that a guy was pushing around (near the fountain by the water where the green grated arch is). I'm 100% sure this is where I got it from, because I was just rolling around trying to get to 3m and I saw it.