Here are two lovely sites, the Official Cyd Charisse site (click "For Fans of Cyd Charisse" above) and Legs: A Tribute to Cyd Charisse.
The official site includes a listing of all Cyd's movie dances, choreographers, and dance partners.
It's difficult to name a favorite Charisse film or number. I think of her small but memorable role as sweet Deborah, one of the HARVEY GIRLS, or dancing "Blue Room" in WORDS AND MUSIC. Then there's her fiery dance with Ricardo Montalban in FIESTA; Montalban is not usually thought of as a musical dancing star but he was one of her most effective partners.
Besides the obvious dances from SINGIN' IN THE RAIN and THE BAND WAGON, I adore "Fated to Be Mated" and "Red Blues" in SILK STOCKINGS. There are more great films, more dances...but if pushed I think my favorite Charisse role was as Fiona in BRIGADOON, dancing "The Heather on the Hill."
A roundup of links:
Self-Styled Siren has a tribute posted.
And here's the New York Times obituary, as well as the Boston Globe's obituary and a tribute in the Washington Post.
Here is another appraisal of her career from the New York Times.
Turner Classic Movies has announced they will preempt their previously planned schedule Friday, June 27th, in order to pay tribute to Cyd Charisse. TCM will be airing SINGIN' IN THE RAIN, THE BAND WAGON, and SILK STOCKINGS.
Previously: Cyd Charisse Has Passed Away.
Update: Here's one more excellent tribute, from the TCM movie blog.