Reference books, including encyclopedias, can give you an overview of your author's life and publications that are more objective than the glowing biography on the author's or publisher's own website.
Search for your author's name in Gale Literature to find a biography of your author.
Tip: Pay attention to the date when your entry was published; some of these are quite old!
Additional background
You can also search these databases for encyclopedias about your genre or theme, to see how your author fits in to the broader literary context: