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