You guys have a nice site here. I belong to a forum community for an online game, and i use ther pics you guys have here as backgrounds for image sigs for ppl (and me occasionally). Thank you guys who run the site and who upload the sweet images. Keep 'em coming.
Well, I'm no expert on copyrights. As far as my country and the UK is concerned you do not need to apply for copyright. Copyright is automatic. I don't know about other countries though.
This might provide some insight:
What is Copyright?
"Before you go any further you need to know that there is no official register for copyright. It is an unregistered right (unlike patents, registered designs or trade marks). So, there is no official action to take, (no application to make, forms to fill in or fees to pay). Copyright comes into effect immediately, as soon as something that can be protected is created and "fixed" in some way, eg on paper, on film, via sound recording, as an electronic record on the internet, etc.
original literary works, e.g. novels, instruction manuals, computer programs, lyrics for songs, articles in newspapers, some types of databases, but not names or titles (see Trade Marks pages);
original dramatic works, including works of dance or mime;
original musical works;
original artistic works, e.g. paintings, engravings, photographs, sculptures, collages, works of architecture, technical drawings, diagrams, maps, logos;
published editions of works, i.e. the typographical arrangement of a publication;
sound recordings, which may be recordings on any medium, e.g. tape or compact disc, and may be recordings of other copyright works, e.g. musical or literary;
films, including videos; and broadcasts.
So the above works are protected by copyright, regardless of the medium in which they exist and this includes the internet. You should also note that copyright does not protect ideas. It protects the way the idea is expressed in a piece of work, but it does not protect the idea itself.";
The copyright agreement on this site states the acceptable usage of the images.
If you ask permission from the authors (and I bet you most of them will say "yes"), then you won't have any problems.