Libraries that have already been wrapped with BuckleScript bindings are customarily prefixed with bs-
, e.g. bs-director
. Here's a search for all of the BS related libraries on NPM.
Take a look at reasonml-community to see a list of curated bindings to JS libraries. And the index which tries to keep track of non-curated bindings and libraries too.
If you can't find what you're looking for: sometimes you don't need a binding to use a JS library. Most JS data types, such as array and objects, map over cleanly to Reason and vice-versa. You also have access to the familiar JS API. Be sure to also check the "Interop" and "Converting from JS" sections here!