I can't find Suicune

[Parasol Kirby]

Yeah it works like Latios and Latias. I got mine completely by accident, but if you were to try looking for it, here's my advice:

First understand how it moves. Like Raikou said, it's only found in Kanto. Whenever you fly anywhere, it warps to a random spot. Whenever you move into a different route/city (as in it says where you are in the little white box in the top left), it will move to an adjacent route. However, it skips over cities and towns. It can be found on water and in grass but not in caves.

Now that you know how it moves, Raikou's repel trick should make more sense. I would suggest Super Repel over Max Repel, 'cause Max Repel is a rip-off (just figure out the step-$$$ ratio of the two), and when it runs out, go into the nearby town and come back out and reapply it. That'll make it move.

Once you actually encounter it, I really hope you still have your Master Ball so this nightmare can end there. If not, I would suggest a Wobbuffet at level 49 leading your team. There's no way defensive, poor moveset, wild Suicune is going to KO a Wobbuffet even with 0 IVs in two turns. This gives you at least a every-other-turn opportunity to throw a Pokeball, while on the other turns you heal. I also suggest giving Wobby Leftovers.

If the above isn't working, you could try weaking Suicune with Mirror Coat, but be REALLY careful. If that still doesn't work, switch in something with False Swipe/*insert fav sleeping move here* and use the move. Of course it'll flee after you hit it, but if you waste all your Pokeballs the other way, I guess you have no choice...