I am new in this site and I want to know that which one is the best site for free use the graphics design ?
(https://www.simplemachines.org/community/proxy.php?request=http%3A%2F%2Fwww.katzy.dsl.pipex.com%2FSmileys%2Fillogical2.gif&hash=e2de730cfaf903097d3e5a30ea407d6511da7208)
Graphics design is completely something else.
I suppose that you meant the best website for SMF themes.
First you'll need to see what kind of theme you need, it completely depends on your own needs and what your website is about.
On the other hand, if you want a fully customized website with own graphics you could ask here for help: http://www.simplemachines.org/community/index.php?board=50.0.
Most likely you'll need to pay for it.
Here are some free themes: http://custom.simplemachines.org/themes/
There are also some several other good websites not related with this website such as dzinerstudio.