There's another special on DSS tonight, (Sunday, 5 March) on Discovery Times channel at 10 PM Eastern.

There were two other recent specials on DSS in the "Heroes Under Fire" series; one was on Port-aux-Prince (involving the Mobile Security Deployment team, the ninja-guy organization inside DSS), and the other was on Liberia.

There's also an older special from A&E called "In the Line of Fire" (or perhaps part of a series by that name) which covered protective details for Madeline Albright.

Last thing I know of is a DVD, "Badges Without Borders," which is part of the "Elite Special Forces" 3-DVD set. Pretty cheesy, IMHO, but has some decent info and interviews buried in there.