need curl tutorial

Hi. Can somebody point me in the direction of where I can see some good examples and tutorials (manuals) for using PHP curl functions? The PHP-manual for curl functions is a bit inadequate for my experience level. I am new to curl but have it compiled and functioning into PHP. I would like to use it to access various sites - most of which are either https or which require the presense of a cookie containing encrypted username/password sets. Any help would be appreciated. Thanks. Lee Howard