Awk to get all my regular users in shadow

You need to escape the $, as it is a special char for "End of Line" much like ^ is "Beginning of Line".

sudo getent shadow | awk -F: '$2 ~ /^\$/ || $2 ~  /^!\$/ {print $1}'

All users with a password set can be listed like this:

getent shadow | egrep '^[^:]*:[*!]:' -v | cut -f1 -d: