Getting Rare and Legendary Pokemons
Shiny Pokemons: They are randomly found everywhere in the Hoenn Region. In every game you play, a different kind of shiny Pokemon is found like a Shiny Zigzagoon in Route 103 and a Shiny Numel in Jugged Pass. I guess it's all in luck...
Other Pokemons in other Regions: Trade a Pokemon from a fake version that was supposed to be Pokemon Ruby to a real Pokemon Ruby. You can also get others if you have a Pal Park in Pokemon Diamond and Pokemon Pearl. The Pal Park allows Pokemons to be traded from other versions.
Beldum: After defeating Steven, go to Mossdeep City and visit his home. You'll see a letter and a Pokeball on his table. The Pokemon inside is a Beldum.
Heracross: get an Acro Bike (The one that jumps) and then go to the Safari Zone. You'll find a white lane that can be crossed with a bike. Use the Acro bike to jump through then the area there is loaded with Heracross.
Chimecho: Go to Mt. Pyre then find a Chimecho at the grass area near the alders at the top. You'll encounter a Chimecho there.
Wailord: It's almost impossible to get one if you're doing what the Pokedex says. The easier way is to catch a Wailmer that's level 39 and above then feed it with a Rare Candy.
Corpish: Fish using a Super rod in Route 117. You'll get a Crawdaunt once it is level 30.
Regice: After the Sealed Chamber conflict, find the Ruin Maniac Between Petalburg and Dewford while surfing. The ruin is near the ruin maniac.
Regirock: After the Sealed Chamber conflict, go to the South in the Dessert and you'll see a ruin. Once you faced the wall with Braille, go 2 steps right and 2 steps down then a door will open...
Registeel: After the Sealed Chamber conflict, find the ruin Maniac nearby the Safari Zone. Once you faced the wall with Braille inside the ruin, go to the center then use Fly. A door will open...
Latios: After defeating Steven, watch the news in your living room and there will be a report of a blue Pokemon spotted. Then first search nearby route 118 and wait for a Latios to come.
Deoxys: Trade for a Deoxys in a fake version for an easier step.
Jirachi: (I think) you need to win a Nintendo contest to get Jirachi...
Kyogre: Trade for a Kyogre in Sapphire.
Rayquaza: Well, it's makes most people lazy to type it so just read the August issue of K-zone 2007 in the Philippines.
Added by: 11th akatsuki Oct 26th 2008, ID#12432