http://www.animationfactory.com/animations/

-A few are for free

http://www.animationlibrary.com/a-l/

-Animations

http://www.cartooncottage.com/

-Grouped by theme

http://www.animateit.net/

-Requires free membership signup

http://www.millan.net/anims/giffar.html

-Many free animations

http://members.tripod.com/~doxie_44/school.html

-School animations

http://jsmagic.net/school/

-School animations