Don't use Nick_W's first suggestion unless you want to ban ALL good bots from your site, which I don't think is your intention. His second suggestion would also work, but has the downside of telling the whole world the name of this secret page.
I suggest protecting a subdirectory using the sample below, and then putting the page there and giving it a more-or-less unguessable name (i.e. not index.html). Also make sure that if someone nosy tries to access that directory, that your server doesn't cough up a list of the files in the directory. That should be sufficient unless the data is really sensitive, in which case you should definitely password-protect it.
One trick I've heard is to link to the new url using a button.onClick command or a nested form with a submit button to go to the page in question. Most robots (and please correct me if I'm wrong) don't follow these types of links.