For summoning, it is one of two tertiary ingredients used in infusing Wolpertinger pouches, the other being Wolf bones.
Wild rabbits may be found in Isafdar, Miscellania, and the Lumbridge Crater, they will drop this meat on death. You may also find rabbits wandering around the Enchanted Valley (Fairy code BKQ). These rabbits will not display a level in the right-click options, but they have exactly 1 life point. White rabbits are found in Piscatoris and will drop raw rabbit meat (along with hunter-specific items) when caught.