Screencaps and Scans
(Toons and other animation)
American Dad!

Aqua Teen Hunger Force
Big Butt Girl - ep. 85 "Fry Legs" - Fat

Ben 10

Codename: Kids Next Door
Numbah 3 and Numbah 5 fattened - unknown episode - WG
       

Danny Phantom

Dexter's Laboratory

Ed, Edd, 'n' Eddy

Family Guy

Fillmore!

Futurama

Hi Hi Puffy AmiYumi

Invader Zim
Gaz - ep. "Gaz, Taster of Pork" - WG

Jimmy Two Shoes

Kappa Mikey
Lily after getting fat - ep. "A Christmas Mikey" - Fat

Lilo & Stitch

Lucy, Daughter of the Devil
Lucy appears fat in a mirror - ep. 10 "Satan's School For Girls"

Sabrina: The Animated Series

South Park
Large strip club dancer - ep. 140 "The Return of Chef!" - Fat

Stripperella
Girls getting fat - eps. 1-2 "Beauty and the Obese" - WG

The Mighty B!
Bessie stuffed - ep. "Super Secret Weakness" - WG

The Cleveland Show

The Simpsons

Totally Spies

Wayside
Maurecia water inflation - ep. "Slo Mo Mo" - Water Expansion

Xiaolin Showdown