I'm grateful to the list, as I received many excellent and useful replies. Here is a summary of the responses, although I believe you can read most of them in detail with the technical elements on previous digests. Forgive (and correct) me if I misinterpreted your explanations.
The "cache problem" issue: When somebody Googles us, a dead page appears at the top of the results list so visitors are directed to a page not found page.
There are basically two sorts of explanations for the "cache problem," and I think my situation involves both.
P1) It's coming up because other websites still link to the page. Unbeknownst to most (but beknownst to you guys), Google not only shows pages it searches, but also pages that it finds links to. The page tour.htm alone has 200 pages that link to it. You can see these by putting the following into the Google search.
link:www.pearl-s-buck.org/tour.htm
P2) Our server is not configured to send a 404 response code, but a 302 (document moved) code to redirect to the "page not found"; page. Google probably doesn't realize that this 'page not found' page is actually not a page it should cache. To a googlebot, it looks like the page is still there.
Options for addressing the problem(s):
S1) Stop search engines from indexing the page with their crawlers. You can edit your robots.txt file (see http://www.robotstxt.org/wc/norobots.html for more on that) so that search engines would (eventually) stop indexing that page. Or you could take advantage of the fact you're ranked highly and just redirect to your home page from the tour.htm url.
You can get these links removed by going here (by the way this is only for removing 404 pages)
http://services.google.com:8882/urlconsole/controller?cmd=reload&lastcmd =log
S2) Allow the crawlers to index the bad page, but set up one of several kinds of redirects to the new page.
For example: utilize a properly implemented 301 redirect (as opposed to a 302). The 301 redirect instructs search engines that the page has (moved permanently"; engines generally honor this command by dropping the original page and updating their directory with the new page specified in the redirect. So in this case, you could use the 301 redirect to essentially tell the search engines "get rid of this page and replace it with this page.";
S3) Allow the crawlers to index the bad page, but ask websites with links to it to change the link url to the correct page.
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