It's a physical address [1] and in the radio show they actually visit it. They describe the location as being a little eerie:

The office was in a corridor where all the other doors looked exactly the same —locked, nameplates over the door, no light coming out. It was a corridor of silent, empty offices with names like "Software Rights Archive," and "Bulletproof Technology of Texas."

[1] 104 E. Houston street, suite 190, Marshall, Texas