ppm will always be present if you installed ActivePerl. Installing DB_File is as easy as this:

C:\>ppm install DB_File
Installing package 'DB_File'...
Bytes transferred 406934
Installing C:\Perl\site\lib\auto\DB_File\DB_File.bs
Installing C:\Perl\site\lib\auto\DB_File\DB_File.dll
Installing C:\Perl\site\lib\auto\DB_File\DB_File.exp
Installing C:\Perl\site\lib\auto\DB_File\DB_File.lib
Installing C:\Perl\site\lib\auto\DB_File\DB_File.pdb
Installing C:\Perl\html\site\lib\DB_File.html
Installing C:\Perl\site\lib\auto\DB_File\autosplit.ix
Writing C:\Perl\site\lib\auto\DB_File\.packlist

C:\>
[download]