You can start with encouraging foraging by wrapping nuts and treats in paper and work up to more challenging toys. This teaches them to work and play on their own when you aren't home. There are great examples of how to make them on youtube. Make sure that you know what woods you have before giving it to your bird. Acyrilic toys are expensive, but last forever and are colorful. Most birds will chew wood that isn't colored and this reduces chemicals from entering your pet. Experiment with materials such as vegetable tanned leather, stainless steel chains and sisel rope to see which your bird enjoys. Make sure to use a variety of types of toys, grooming, foraging, destruction (wood blocks ect) and rotate them in your cage to keep interest. Ebay can be a great resource but make sure it is a trusted seller. Have fun making them and keep variety, its the spice of life!