I have good links with talented UI designers, but for pure unadulterated graphic design brilliance, I am a little short.
Is there a website where some of these pixel gurus live and show their work? UK specific would be good, but not essential.
Try these two...
The forums at http://www.designerstalk.com/ are also quite busy!
http://dribbble.com/ is a great place to see people showing of their work, plus you need to be invited to dribble, so everything is perrt darn good
There is http://sortfolio.com/, which was created by 37 Signals. It is US and Canada only right now, I think.