writing a spider in PHP

[discombobulator]

Can someone point me in the direction of an article to show me how to write a spider in PHP. Essentially I want to type a URL and get the unrendered HTML code returned into a PHP variable.
I can do a 'view source' in IE and see the source code in notepad but I really want to get the source into a PHP variable.

Thanks for your help.

[discombobulator]

I have just found out how to do this.

$lines = file ('http://www.example.com/');

It was in the manual all the time !!