Cartoonretro is an interesting subscription site at $5 a month. It's a new project from Shane Glines, creator of the Cartoon & Illustration Paradise website. Cartoonretro is devoted to celebrating and exploring the largely forgotten work of great artists, cartoonists, illustrators, photographers, filmmakers, actors, musicians and industrial designers from approximately 1925 through 1939.

Also of note is the Cartoon Brew blog which covers in depth animation in America. Most recently they had an interview with John Kricfalusi.