Hello clayton! I recently bought (pokemon heart gold) just the cartridge off Amazon and there are combo cases you can buy from most local retailers like wall Mart, game stop, etc. That you can place more than one cartridge in and carry all your favorite games in at one time makes it easier to access, instead of just going case by case. Unless you like to stay completely organized on a shelf, but if your anything like me I'm constantly back and forth with my games, so any combo cases make my life allot easier... i hope this helps. If you can't find it in store look online for them. Good luck!
Because they stopped producing it. The value of the game went up while the quantity went downs so if you happen to come across a brand new version it will be expensive. This is Pokemon and it is a collectors item.