First, contact the stove manufacturer. If they do not have a manual available, they will refer you to a website where you may download the manual. If this is not successful, you should advertise in newspapers under the wanted section.
Pellet stoves are sold at places such as Best Buy, Menards, or Lowe's. You can call your local store to see if they have them in stock before going there to buy one.
This question is not clear enough because we don't know what part of the stove is broken. But if the stove isn't working,then I suggest you buy a new one.