Introduction to writing spiders and agents
Spiders can be written in nearly any language
   1. Java
   2. Perl
        http://www.cpan.org
   3. Tcl/Tk
        http://www.scriptics.com
        http://www.webtechniques.com/archives/2000/03/schrenk
   4. PHP
        http://www.php.html.net
   5. cURL
        http://curl.haxx.se
        http://curl.sourceforge.net