# perl -e 'print join "\n", @INC'
To find the path of each individual Perl modules:
# find `perl -e 'print "@INC"'` -name '*.pm' -print
To check if a given Perl module is installed on the system:
Let say you want to check if the Perl module "File::Compare" is installed or not. The syntax would be as follows:
# perl -e 'use File::Compare; print "Installed\n"'