Sary:

If you just want a web crawler, I'd suggest you start with LWP or WWW::Mechanize so you can avoid the socket details. But if you want to attack your problem from the socket level to learn, then I'd suggest you get a good reference on socket programming to learn a bit more about the subject. Writing code for something you don't understand can be frustrating. While I'm certain that the University of Google can get you started, I recommend the Stevens book on UNIX network programming, check out the sample chapter referenced here. Even though it's for UNIX, most everything translates nicely to Windows as well.

The same author has several other books on networking that may be interesting to you. (Note: I have no relation with the author, save having purchased, read and enjoyed the book I recommended.)

...roboticus

When your only tool is a hammer, all problems look like your thumb.

Update: Repaired second CPAN link.