The credits cover whatever I could find from the major newspapers (esp. the New York Times), from two book series Guernsey's Best Plays and Willis' Theater World, and from the Web.
Ms. Clarke also did regional theatre. There are no doubt performances, which she had done in other parts of the country in the pre-Web days, and which have slipped past both Willis and Guernsey.
As examples, Ms. Clarke did summer stock and local (Pittsburgh-area) theater after her graduation from Mount Holyoke, and the article Movie Brings Caitlin Clarke Back to Her Roots
by Ed Blank (The Pittsburgh Press, 3 August 1985) mentions two plays she did then. Only one, One Flew Over The Cuckoo's Nest by the Pittsburgh Public Theatre during its very first season, can be verified from the Web.
Ms. Clarke also performed in The Seagull, as mentioned in her credits on the web site of the play Titanic: A Musical. It's only a guess, but I believe this was the Guthrie Theatre production during its 1983-84 season, with David Hyde Pierce as Treplev. I also now know that she also performed this play while she was a graduate student with the Yale Repertory Theatre.
The question I most pondered, besides whether Ms. Clarke knew about this site, is whether this site is accurate. The information in this site is taken from second-hand sources: reviews, compilations like Willis and Guernsey, and the rare interview.
I learned from more than one correspondent that Ms. Clarke was happy with this site. I will take it to mean that the site is accurate enough to please her, and that is sufficient.
This gets its own page: Personal Addresses.
By this I'm talking about such things as the forest pool scene in Dragonslayer and the dressing room scene in The Mayflower Madam. You will have to take my word for it, that Ms. Clarke is a woman among women.
A certain fan e-mailed me, asking (apologetically) whether it was really Ms. Clarke or a stunt double in that forest pool. I had replied that Ms. Clarke had a nude scene in Bal at Chicago's Goodman Theater just before production of Dragonslayer; so I doubted that she would have been shy about doing a nude scene if the scene required it. She would not have done it for long, anyway: That water must have been cold.
(I have since learned that, no, it was not Ms. Clarke but a stunt double. Sorry, folks! — aw, 18 April 2013.)
For anyone who has not visited an animé or idoru site, these refer to a person's age, height and weight; bust, waist and hip measurements; shoe size; and blood type (which is supposed to indicate a person's general character). In Japan even male actors and singers are so measured.
Ms. Clarke, like any normal American woman, would go ballistic if she were asked for such info by a total stranger without good reason. Even if I had these stats, I would not publish them. I prefer not to be ground zero.
You can observe from her films that Ms. Clarke is short and slim. You can reckon Ms. Clarke's age and astrological sign (Taurus/Venus/affectionate, patient and dependable) from her birthday. For the rest, you can get an idea of what Ms. Clarke is like from the Favorites page.