The library's databases are also a good source of author interviews. Use ProQuest or Academic Search Complete, linked below.
Be sure to limit by document type, such as Interviews, or try adding Interview as a search term along with the author's name.
This image below shows this example in ProQuest
(click on image to enlarge)
In the same way that you would search in the databases above, limiting by document type - so too can you search many of the other databases, including Gale Literature.
You can search for author interviews online using Google. Simply search by author name and the keyword: Interview