Where to Find and Catch Volbeat
From Pokemon Go Wiki
Volbeat are found and captured in Nest and Habitat locations.
Nests
Volbeat Nests are locations that consistently spawn Volbeat.
Habitats
Volbeat Habitats are spawn locations where Volbeat 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: