I couldn't navigate through this site either. I kept getting the message, "You are not authorized to view this page." However I was able to search it using Google's Advanced Search function.

You can use their fill-in-the-blanks form (click the previous link) or you can search by using this URL:

http://www.google.com/search?as_q=CHORUS&as_sitesearch=WWW.HAVEN.ORG

In this case WWW.HAVEN.ORG was the site I wanted to search and CHORUS was the word I was searching for. (The words don't have to be in caps.) This technique works with almost any web site.

Also, when the Results page came up, I had to click on "Cached" to see the page. Otherwise I got the same old "You are not authorized to view this page" message!