First, as I am wont to do, HDS will link the hub of his collective.
Here we have the entry for Sakuya at Wikipedia. Most of what is covered there I cover here but, given Wikipedia's transient nature, this may not be the case for long.
A Sakuya shrine that is, sadly, abandoned. The owner shut it down but left it up for as long as Geocities chooses to allow its existance to continue. Even in its closed state, SKS contains a great deal of media, including many pictures that I have here (Although I am reasonably sure I got the ones I have here from elsewhere.).
Animated Lust has, as one of its many character pages, one on Sakuya. It has information, quotes, pictures, and links to more pictures. It also has the English and Japanese lyrics to what is caller Sakuya's "Image Song." Plus, how often do you get to use a link button with The Red Guy in it? X3
The Pantransit Usenet Anime Images Archive
This is a site that once was vastly larger, housing many hundreds of images from many scores of series. However, soemtime between when I grabbed most everything, which was eons ago (This is one of the older sites I've grabbed things from that is still in operation), and 2004 or so, many of the images disappeared, including anything on Sakuya, of which there were a number in the Tenchi Muyo section. I link to that now out of respect for what once was there.
Shadows of Sakuya Kumashiro
Shadows of Sakuya Kumashiro is another of the older sites dedicated to her. Some information on Sakuya, quotes, and a blurb about her seiyū, Mayumi Iizuka.
Sweet Sakuya Dreams
Once one of the larger and more complete Sakuya shrines, SSD was struck by a hacker attack that eliminated all but the front page. While the hackers eventually restored the webmistress' access to her site, it seems that the attack had taken with it not just the site but her will to rebuild as well. I include this link as a memorial, due to the site having been abandoned for many years. However, I was able, through some guessing, able to locate two pages on the site that remain up, albeit not linked two. One is what appears to be a former information page on that website, although a number of the links within are broken. The second appears to be the server generated folder index of the webmistresses image directory, which still contains a great many images.
The Tenchi Muyo Information Archive
A general TM information website, containing a Sakuya bio and some pictures of her.
Crissy's Sakuya Bio
Biography of Sakuya at "Crissy's Cray-Z Cite."
Sakuya Kumashiro's Destiny
SKD has been and remains one of the more complete Sakuya sites around. It is from here that my mirrored screencap gallery gets its material, and I believe several other images also originate from there. Much is to be found there!
Tenchi in Tokyo
A general TM information site. Not all links work, however. It is from this site that HDS gathered some information used in his long Sakuya bio.
The Ayeka Fan Club
An ezboard forum from where HDS gathered a number of the nicer and rarer pictures that are located here at Reflections. I've tried to cite specific page addresses with each applicable picture and I think I covered all from here.
Jen's Homepage
This is the homepage of the source of most of the lovely scans found at the Ayeka Fan Club, Jen. If you at all like Tenchi Muyo, check her site out, as it has much more on other Tenchi characters that I did not place on this site.