One of the major benefits of Perl is CPAN, which allows us to not re-invent the wheel. So have a look at File::Find::Rule. It will do all you need.
in reply to search folder and delete certain files with perl
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James