There seems to be a lot of discussion again about whether you should post sample pages on your Web site and tell an agent about it in your query. Obviously different agents are going to say different things on the issue, but ultimately, if your writing is good, no one is going to reject you simply because you’ve posted a chapter or two on your Web site. What they might do, however, is reject you because your entire query letter says this:
Dear Ms. Faust:
Please read my amazing new book at www.bookends-inc.com.
Your Web site is another address and promotional tool for you. Posting pages can help attract agents. I know that when I see an author’s name again and again in contest wins, on my blog, or as a conference attendee, I’m going to look for a Web site and I’m going to read any pages that are there. Never will I contact an author out of the blue if I haven’t read her work. However, if I’ve had the opportunity to read a sample chapter on her Web site, I might think it’s good enough to ask to see more.
One of the concerns I've been asked about is how a publisher feels about authors posting a chapter on the Internet. There seems to be the feeling that publishers will then consider the work published and not touch it. In other words, putting a chapter up on a web site ultimately means that you self-published the book. Not true at all. I have never had a publisher ask me if a chapter was published. In fact, most will encourage authors to promote using that tool. Should you post your entire book? I would recommend against it. Think of it as promotion. You wouldn't promote your book by posting the entire thing therefore you shouldn't promote your unpublished work any differently.
I honestly don't see any cons to posting a piece of your best writing on your Web site. It gives people the opportunity to really see what they can expect from you and, you never know.