While figuring out how to manage my pics, and easy insert into my blog post, I found this plugin. Picasa LigthBox 2. This plugin will retrieve our public pictures from picasa gallery, and have an easy interface to include them into our blog post. Besides, it provides a overlay preview to our users, using WordPress Lightbox Plugin.
Just put the WordPress Lightbox2 plugin into your wp-content/plugins/, activate it in WordPress Admin page. Do the same thing for Picasa Lightbox 2 plugin. Put into your plugin folder and activate it. After that, you can see a small button to add new picasa photo.