Udon are localizing a series of artbooks for Fate/Stay Night, the first of these being Fate/Complete Material Volume 1: Art Material. This first volume will be available in June 2014.
Fate/Complete Material Volume 1: Art Material will feature illustrations, character designs and concept material from Fate/Stay Night, including cutscene illustration, pin-ups, promo art and more. Following the release of the first volume, the rest of the books will be released every 3-4 months.
Udon say that sales of Volume 1 will determine whether or not future volumes in the series of artbooks will be brought over.
You can click the images below to look at some of the pages from the book.