You can search Worldcat UMD just like you would Google. Just throw some words in there. Try combining your chosen artist or choreographer with a work, such as:
For simple searches for a composer or choreographer, you may want to add "su:" to your search, which will find only books and articles about the person, rather than items by them. For example:
If you need to narrow down the results of a Worldcat search, use the filters on the left-hand menu, like "Format:"
The "Availability" section of an item, such as this book, is especially important if you are in urgent need of it (it is checked out until February 16th, so I would need to request it from somewhere else):
Worldcat will let you know when an article is available to view online by displaying the "View full text" button: