The answer to your problems is
CGI.pm. This is standard with your perl distribution. You will only run into problems if you try to parse your query string. CGI.pm does this all (correctly) for you (and much more). IOW you are asking for a world of trouble if you avoid CGI.pm :)
I would also recommend
Ovid's excellent tutorial on
CGI programming with perl
Also to keep yourself in good standing at perlmonks I would recommend a couple of things.
read the literature on posting - turnstep's node is excellent at explaining many things a new monk should know.
always search before you post. I turned up many hits with query string. Pretty much saying the same that I am telling you.
Know thy FAQ
grep
|
grep> chown linux:users /world |