Exclude hidden files when searching with Unix/Linux find?

It seems negation glob pattern is not well known. So you can use:

find . -name "[!.]*"

I found this here:

find . \( ! -regex '.*/\..*' \) -type f -name "whatever"

This doesn't answer your question, but for the task of finding non-hidden files I like to let find find all the files then filter with grep.

find . -type f | grep -v '/\.'

Similar to your approach but perhaps a bit simpler.