Sorry, but you cannot find Arbok or Ekans in the wild, you would have to use the PokéTransfer Lab or go through the Dream World.
yes.
in Pokemon leaf green red blu and gold
Yes, you can get Arbok in Pokémon Black however you cannot naturally find Arbok or its pre-evolved form of Ekans in Pokémon Black, the only possibilities to acquiring Arbok in Pokémon Black would be PokéTransferring it from a previous compatible game or trading with another player.
you can get zangose insted of arbok . you can catch groudon instead of kigog
You have to use the pokeradar which you get once you have completed the Sinnoh pokedex and use it everywhere there is grass sooner or later you will find it. Or you can get an action replay and use the Pokemon modifier code and choose Arbok and catch him.
you can catch arbok in the great marsh with firered inserted only 8% of time
arbok doesn't evolve.
to catch zapdos in pokemon black you have to have every legendary pokemon
You can find an Arbok in route 3,4,26,27
You dont catch it in pokemon black you have to evolve it into bisharp
You cannot catch Rayquaza in-game in Pokemon Black.
In Pokemon black you catch RESHIRAM and TORNADUS In Pokemon white you catch ZEKROM and THUNDERUS Sources : myself