Ron

After that experiment gave no clues at all, I looked harder at your link, and it points to a secure web page (https://) so maybe thats the thing that stopped it working.

I'm not sure it is a good idea to post links to secure sites; the extra information after the "?" is used by some sites as a means of retaining user details as you move from page to page. This is not the case with the link you have posted, it look like normal search info. I wonder why this was a secure address in that case - is it a site that only reveals prices to you once you have registered at the site and logged in?