Bengal kittens are available at appropriate breeders, some of which can be found online. It is highly recommended that the kitten be adopted locally, though this isn't always a possibility.
Due to the rarity of the breed, Bengal kittens are often not found at local shelters. However, that is a good place to start. If there are not any available to adopt at a shelter, a good breeder is the next choice. Look into the breeders and be sure they are humane and raise healthy kittens. Searching online is good when trying to find a local breeder and learn more about their practices.