Script for data collection

This is an easy script for an experienced and a professional developer. I need a script, that works as a cron job on Linux server, crawl the web(Google and Yahoo) and collects data based on a certain keyword. The data gets saved in a MySQL database. The script has to work on Linux (Apache Server) -- it can be either PHP or Perl/CGI or other language. The script has to contain comments in the syntax for further improvments. Please apply if you are serious and you can do it. Best Regards, emcon