How to I add a headergrafic?

[JQUEST]

Thanks for the reply,

Please clear me one thing. If you want to add a image in headder like http://sagre.tv/

No.

or you want to add a small image in "SIGNUP / LOGIN" background

Yes,

I want a small graphic as the SIGNUP/LOGIN background.

I could have been more clear.
The suggestion I quoted previously is for an html background and that doesn't work for me.
I need the background to be centered behind the SIGNUP links and not repeating.
So it's gotta be css. Right?

I added the class to stlye.css and haven't been able assign it to a table i put the SIGNUP/LOGIN code in...

I havent had a chance to mess with it since my last post,
I could try a span or div tag instead of a table?

Thanks for your help.