Adding wp_header

I posted a more in-depth description of my problem under the Plugins heading, but maybe it is more appropriate here anyway. All I need to know is how to add the wp_header tag. My theme is working great and I’ve been very careful to set it up with clean code and the simple header, sidebar, footer format.

But now I am trying use a plug-in that requires that the wp_header tag. I call the header template by using get_header and I am wondering if that was a replacement for wp_header or if I just totally don’t know what I’m doing.

Please help. I just need to know how to work in the wp_header tag to get this plug-in (lightbox) working properly.

Thanks.