You can find Suicune, as well as Riaku and Enti on the bottom floor of the Burned Tower. Hope that helped! :)
On Cerulean Cape
Where you find Misty.
Cerulean Cape after finding him on other routes.
You must chase Suicune around until you finally find him at the place where you first find Misty.
chase it then you can catch it find out where it goes on seribi.net
Suicune is not in Pokemon Pearl. Currently you can get it in Pokemon Colosseum and Pokemon FR/LG if you start out with a Charmander and beat the Elitle Four. You would have to migrate it from a GBA game that way. It is said that you may be able to get Suicune in the upcoming games Pokemon HeartGold/SoulSilver.
Houndour, Houndoom, Lillipup, Herdier, Stoutland. Legends: Entei, Suicune, and Raikou. Find them in Pokemon Platinum, Black, Heartgold, and Silversoul.
you go to the ocean/sea (next or in between rout 14 & 15)then you'll see suicune. it'll then run up the water. then a man will come and challenge you to find suicune the fastest.
Find SUICUNE at Route 25 after meeting him around Johto at every place he appears.Route 25 is in Kanto. He is Level 40.
After Suicune there is Regirock. You can find it at Sekra Range.
You find Suicune at Ceruluean Cape.
suicune is on the right side somewhere on route 14. after encountering suicune there, if you met misty at the end of route 25, you'll find suicune there and you can battle it.