You can upload your own local images to the live Artstor database and search them as a collection alongside other Artstor images.
Any user can have his or her own online Personal Collection where images can be uploaded and added to Artstor image groups already available to that user. Personal Collection images can be cataloged and sorted into topics for easy retrieval. Access to a Personal Collection can be restricted to an individual user, or to that user and others at the University. (Please note that neither Artstor nor Brandeis University is screening such content, and therefore the user is solely responsible for obtaining all necessary permissions before loading such images.)
More on Personal Collections (from the Artstor Support site)