Barbara Vey writes about authors on her blog, Beyond Her Book, on the Publishers Weekly web site, and she detailed a number of pet peeves she encounters when she visits author web sites. Are you an author that doesn't have a web site? You already lose major points with Vey.
Some of her other complaints include:
An outdated web site, especially one that doesn't list the author's new releases.
A web site that doesn't offer the reader a way of purchasing a book.
A web site with no blog entries or other communication from the author.
A web site with no information about the author.
I'll also add a few more things I think an author web site should have:
An author photo. Newspapers often contact me looking for an author photo if they can't find an author web site, or a photo of the author on the site. When newspapers carry stories about an author, they want an author photo, along with the book cover photo. Make it easy for them and have the photos available as downloads, along with copies of the press release for the book.
A schedule of author book signings. I'm surprised that many authors overlook this, or don't keep their event schedule up-to-date.
A sample chapter or two of the book. If your book is already listed at Google Books and has a preview, just post a link so potential readers can browse your book.
Vey says it best in her blog post: "To me, being an author is a business and as a business you need people to see the product. What’s available and what’s coming up at the very least. It doesn’t have to be fancy. No need for video or anything flashy. Just something that says I take my job seriously and here’s why you should read my work."