I had a look at your code, but even when not being a networking-guru, I can see some problems:

• You should use strict; and use warnings; to guard against silly mistakes, bad constructs and simple typos.
• It is really a bare-bones, down-to-earth, ultra-simple type of webserver and as little as I know of it, web-servers are all but bare-bones, down-to-earth, ultra-simple kind of things. I'm not sure it is not full of ugly security holes, although you do some sanitizing of the request string.
• It can handle only one connection at a time.
• It can do no authentication / authorization.
• ...

Don't misunderstand me, I am not saying your code is not an honest try at writing (the beginnings of) a webserver, but these things are quite complicated by nature and without a good game-plan you are likely to bump into some issues later on and will have to start all over from scratch.

As I am against re-inventing wheels, personally I would start with an existing design (see the links in my previous post) and adapt it as needed.