Where to find Munchlax in Pearl?
You find by slathering honey on yellow trees but its really really rare to find you find it on certain trees
Munchlax is rare and you need to keep trying but slather honey on one of those yellow trees and after a while of walking around the tree will start to rattle and although from my experiences it has usually been an aipom, I've heard and am pretty confident that a munchlax is in there. It has to be because your rival has one.
Well, you can't get him directly. You will need to happiness evolve him from Munchlax, which you can find by slathering the golden trees with honey, and leaving it for about 12 hours. But the Pokemon which appear are totally random; Munchlax, Heracross, Cherubi, Combee, so don't just do it on one tree and expect to find it.
It's kinda hard, first you have to fly to floaroma town and go to that guy who sells honey, the slam the honey on honey tress (the yellow ones) then waite about... 3 to 6 hours and go find if munchlax is there. PS: Munchlax has a 1% chance of appearing (sorry about the writing, I'm portuguese) on honey trees. So, yeah, good luck, you'l need it...