Block sites linking to my site

From: basin (basin_at_discussions.microsoft.com)
Date: 03/25/05 

Date: Fri, 25 Mar 2005 08:41:03 -0800

We have a site that has a "sample request " form where future customers can
order sample of some of our paper. Well, apparenty some people found it and
posted it on sites such as freesamplesite.com and fatwallet.com. So we have
hundreds of orders for samples!!

Is there any way we can block people coming from this link? I am
understanding that when a "freebie" addict clicks on that link, the ip
address in the log should be that person's IP....but our webtrends reporting
has no problem telling us that we are getting users from these domains.
Webtrends uses the iis logs to get that referrer address and domain,then put
it in a nice little report, but I cannot find it in the logs.

Any ideas?? Thanks for any help!