Where to Find and Catch Munchlax
From Pokemon Go Wiki
Munchlax are found and captured in Nest and Habitat locations.
Nests
Munchlax Nests are locations that consistently spawn Munchlax.
Habitats
Munchlax Habitats are spawn locations where Munchlax is likely to be encountered, but not guaranteed the way a Nest is.
Additional Tips and Information
Best Nests
If you know a really good nest or any of the nests above is really good, list them here: