Since Oprah is a syndicated afternoon show, what time it airs varies from city to city. There is a page on her website where you can type in where you are and it tells you what channel and time it's on in your area (although you may have to figure for yourself what CABLE channel that translates to):
http://www.oprah.com/tows/program/tows_prog_whenwhere.jhtml;jsessionid=CGPS4NSFZ10AJLARAYIRNWQ
If for some reason that link doesn't work, go to her home page, www.oprah.com and click on the link on the left side margin that says "The Oprah Winfrey Show." On the next page, there is a small link that says "Local Listings," that's the page you want for your schedule.
Also, you should know about Oprah's "After the Show" show. This is DIFFERENT than the main show in the afternoons, it is more informal bantering with the guests after the main show is over. It airs the same day on the Oxygen cable network, at 7:00pm ET, and repeats again at 10pm ET. Don't know for sure if they will cover Terri further on this After Show, but it's possible.
[sweetliberty, I just pinged several names, not anywhere near the whole ping list.]