Here are a few sites and blogs which have featured feminist cartoons or written feminist critiques of cartoons.
Out of the Locker – a critique of Disney’s Kim Possible
Nina Paley, creator of Sita Sings the Blues
Feminist Allies – a critique of Disney films’ characterizations of masculinity
An article about the first feminist cartoon: Betty Boop
Feminist Mormon Housewives (yes, that’s what it says) blog post
Women’s Cartoon Index (List of women cartoonists of all kinds)