Ogre bellows are obtained by "unlocking" a chest (a key is not required) in the north-west part of the cave (not on worldmap) in eastern Feldip Hills where Ogre Rantz and his son and daughter live, directly north from the quest start icon where Big Chompy Bird Hunting is started (fairy ring code AKS is nearby). Normally only one can be in the player's inventory. However, if you should want more than one, it is possible to use the drop trick.
The bellows are first filled with 3 loads of swamp gas from the swamp to the west. They are then used on the swamp toads found nearby, causing the player to say "Come here toady!". One load is removed from the bellows, and the player receives the message "You manage to catch the toad and inflate it with the swamp gas. You add the bloated toad to your inventory." Only three toads may be carried at any one time, though more than three may be laid on the ground.. If the bellows have no more loads of gas, the toad displays "Hissss...." in public chat, and the player is told "The air seems too thin to stay in the toad. Perhaps you need something thicker than air." The now incapacitated bloated toad may be placed anywhere in the ogre area to attempt to attract a Chompy bird.