The legendary dogs Raikou, Entei and Suicune does not exist in Pokemon Emerald, the only way to get them is to trade them from Firered or Leafgreen, but also there you can only get one of them, it changes of what starter you choose, Bulbasaur-Entei, Charmander-Suicune, Squirtle-Raikou, and they're relised after you complete the Pokemon leaguage.
Any other Pokemon questions, check out Psypokes.com or Serebii.net
If you count sudowoodo as a legendary then yes
all the legendaries and how to get them here http://www.psypokes.com/emerald/legendaries.php
In Pokemon Emerald, Groundon and Kyogre are legendary Pokemon. You can find them in the Marine Cave and the Terra Cave.
Up your butt an around the corner
In general, there are 6 legendary Pokemons in Emerald. If you count the Event Pokemons in Emerald, then there are 12 legendary Pokemons in Emerald.
its not an emerald its RAYQUAZA the main legendary Pokemon in Pokemon emerald.
YOU FIND RAQUAZA IN SKY PILLARYOU FIND RAQUZA IN SKY PILLAR
they are the three legendary pokemon of rock, ice and steel. they are know as regirock, regice, and registeel. you can find them in Ruby, Saphire, and Emerald.
You'll have to cheat(which is ashame) OR use a walkthough to find out
None of the legendary dogs are available in Emerald you must obtain them from Firered, Leafgreen, or Pokemon Colosseum.
Unfortunately you cannot get the legendary dogs Entei, Suicune, and Raikou in Emerald Green. You can import them into Emerald green by trading from Leaf Green and Fire Red.
they have to be migrated from pokemonSilver. they cant be found in emerald.