Your site has many issues, firstly your jquery is not loading correctly. If I look at what your server is giving me I expected to find a minimised copy of jquery, instead I got a html meta refresh tag.
Because of this, I then get around 10 errors caused by a missing jquery library.
Then, if you look in the tags of your site, you'll find the references to jquery.lightbox.js, the nonexistant file you are seeing.
I suggest disabling the lightbox-gallery plugin, and opting for an alternative. I would also cut down on the number fo scripts and stylesheets either by merging them or removing them.