LibX is a Firefox or Chrome plugin that enables direct access to the user's library's resources, including support for Google Scholar, CiteULike, COinS, and xISBN.

Users can search their library catalog(s) and databases through a search bar or through a context menu.
Presently it is no longer supported on Chrome (and maybe also Firefox) but it is supported by Internet Explorer. The latest release was in 2013 so it might not be compatible with recent releases of Internet Explorer.