When youre versing the champion
after beating the elite 4 go find it
go to the snow or water or forest then look to you find him!
Find a specific route or cave to train your Pokemon in and stay there for a long time.
Go train your Pokemon get stronger then go back beat the elite four and go kick alders butt!!!!
You can't catch a Munchlax in Pokemon Black or White, you can use the PokeTransfer on Route 15(after beating the Elite Four) or you can go to the Villa in Undella town(also after beating the Elite Four) and there is a gouy in an orange shirt with brown hair that wants a Cinccino, if you trade to him you will get a Munchlax level 60, But to get a Cinccino, you need to catch a Minccino and use a Shiny Stone on it, and to get the Shiny stone you need to go to Dragon Spiral Tower and it will be in a pokeball there. Sources: Officail Pokemon black and white strategy guide, and I've beaten EVERYTHING there is to the game
At 'N's Castle after beating the Elite Four.
You find him in meteor cave after beating the elite four.
you can find it in pinwheel forest after beating the elite 4 (.)(.)
The Pokemon League after beating the Elite 4.
Recieve it from Elm after beating the Elite 4
after beating the elite 4 go find it
after beating the elite four, it can be found in meteor falls
After beating the elite 4 he/she randomly appears in the wild so you have to find him/her
new safari area after beating the elite 4
To get Celebi into a Pokemon Black or Pokemon White, you must transfer it via Poketransfer, which is only usable after beating the Elite Four. Follow the route to the right of Nimbasa town, cross the bridge, and you will find it :)
there are a lot of neat Pokemon in the safari zone. after you beat the elite four you can get latias , (kyogre b4 beating elite four), and i heard a rumor you can get mew in it
I do not know where he is after beating elite four soul silver. I hope to find him soon.