Rabbits of any age can eat pine cones and cardboard. That's another great toy for bunnies that you don't have to buy. Have leftover toilet paper tubes? Give 'em to the rabbits! They love to throw, chew and play with the cardboard.
I like the kind of toys that can't be completely eaten. Anything wooden a rabbit can completely destroy and you'll have to replace it. With something you buy from a pet store, that can run your rabbit bill pretty high. Sometimes a piece of cardboard/pine cone will only last the night. All the rabbits, especially Cinnamon (below), love playing with balls. She loves to roll things around and chase after them. And the ball below even has a little bell inside! Put some treats or hay in there and it becomes not only a toy but a game!