In a recent mail Mr Bebian was mentioned. Yes, he does have a Wikipedia article in English French and German  and in the English article many of his books are mentioned. As Mr Bebian has Wikipedia articles in multiple languages, there is an "item" for him in Wikidata . The links to these articles are at the bottom of the information about him.
There are two opportunities for you; the first is that you add his name in American Sign Writing to this item in Wikidata. The second opportunity is to make sure that there is a sign for him in any other SIGN language.
For the first opportunity you have to create a #Babel template on your user page on Wikidata. Copy the one on my user page  and modify as needed.
For the second opportunity, you want to know that the Language committee of the Wikimedia Foundation changed its policy; any ISO-639-3 recognised language is eligible for using Wikidata . This means that if YOUR sign language is not enabled, you can request it. It will be quickly granted eligibility and it is then a technical matter of enabling YOUR language.
There are several reasons why this is of interest, the WMF is in the process of changing its search engine behaviour and considers including the information that can be found in Wikidata. This means that they will support any language that is enabled in Wikidata, It means that when a new Wikipedia is created in American Sign Language, all the Wikidata items with ASE labels will be included in the search.
There is already a hack that does exactly this !!
In conclusion.. Wikidata does provide information about more subjects than any Wikipedia has articles. It just needs labels in YOUR language to do its job. If Steve or Valerie is interested in cooperation between Wikidata and Signpuddle, it would make for a really interesting side project. Such a project could become a Google Summer of Code project and have a student work on it (for some money) for three months. <grin> yes, Steve will need to be the mentor of such a project </grin>