Hey guys! I've been looking for cool header image for my site for ages. And, alas, I've found it through searching the net. And the good thing about this site is that you don't need to log-in to download or save the header image! Cool, isn't it? Moreover, they have many categories to choose from.
Here are some of the sample images:
So, without any further ado, here is the site: Free Web Page Headers.