It depends what you mean. If you mean in real life, on Ebay or Amazon. If you mean the games, you don't buy Pokemon, you catch or trade them.
Pokemon can be bought from a variety of places, from local game stores in or around your area, to various online stores. Local stores also often have a website where you can order Pokemon games from home and, as said above, you can always order from Amazon or eBay. Play-Asia also offers Pokemon games of every region and ships worldwide.
In the earlier Pokemon games, some Pokemon could be bought with game coins earned (or bought) at the Game Corner. This seems to have stopped since Generation III games, however.
You do not buy them, you CATCH them.
Yes, you can buy them with credits.
any game store
You can buy Pokemon Ruby on eBay or Craigslist.
You can't buy it, it comes with a pokemon.
Can you buy this pokemon card at Canada? No
You can not buy Pokemon from the game corner in Pokemon diamond, but you can in heartgold and soulsilver
You can buy Pokemon using the gambling coins in Celadon City. The building to buy the Pokemon is right beside the casino
Well if you like them just buy Pokemon diamond&pearl,if you already have then buy Pokemon platinum THEN if you HAVE Pokemon platinum buy Pokemon HeartGold&/orSoulSilver. because Pokemon diamond,pearl&platinum are all alike.
You can buy it at Gamestop.
You could buy them at Target!
you can not buy a moonstone in any Pokemon game but you can find them somewhere