No trainer that you would battle in Pokemon Platinum has a Suicune. The trainers you face in the game use Pokemon that can strictly be obtained through normal gameplay, and do not possess any legendary Pokemon.
Theres a trainer on route 209.
ice type trainer in snowpoint
There is no trainer with it, but you can evolve remoraid at level 25.
there is a trainer at the end of route 217, by Snowpoint City
In the city!
Not unless you cheat.
Trading or cheating.
There is no trainer in platinum that is willing to trade a munchlax.
Sorry but there isn't a trainer with a bagon in platinum.
you can find the trainer with the misdreavus in platinum in hearthome city i believe
no one no trainer has a kingdra in Pokemon platinum exept for me :P
The trainer in victory road
A trainer on iron island has hippotas
A Trainer on route 220
A trainer has it in their party on route 221.
the trainer by that place, you know ? :)
There is no trainer with Lickylicky in Platinum. You can however catch one at the lake near Twinleaf. You will need Surf.