Visit a comparison shopping website such as DVD Price Search, Bizrate or Pricerunner.
Locate the "Search by" box or "Search" box and type in "The Sentinel" as the title you want to price. Select the option that allows you to search for all stores within the website's matrix. Click "Go," "Send" or "Search."
Locate "The Sentinel" TV show in the list that appears on the page. The show may appear in single seasons or as a package set. Click on "The Sentinel."
Review the vendors who sell single-season or series DVD sets of "The Sentinel." Note which vendors charge shipping and handling and sales tax. Note which vendors offer special promotions.
Visit the website of the vendor you select with the best deal to confirm if the price offered on the DVD comparison shopping website is accurate, and to see if there are any updated deals that might reduce the price.