Blender , which is free, now has an script or plugin that exports as swf.(flash)
I dont know if it's 100% done
But Blender is not easy to learn...
A comercial package is largely used for this.called swift3d.
And in the best place for flash (imho, besides were-here.com ) ,flashkit.com you have a board section, full about 3d in flash...http://www.flashkit.com/board/forumdisplay.php?s=f75874506af3991860dfa7a2af881b86&forumid=16
While I don't like anime, some very good pieces are seing animated and drawn in same boards, in art&anime section.
Once you're there...