Booth 101
From Homestar Runner Wiki
Booth 101 is where Strong Bad and The Cheat sold "gamertags" at Trogdor Con '97. The booth has a wooden top with blue curtains draping off the sides of it. On the top right of the booth, there is a white sign reading "booth 101". On the wooden top there is a sign reading "gamertag?" Behind the booth are boxes labeled "GAMERTAG?", and neither Strong Bad nor The Cheat know what's in the boxes. There is a white banner hanging behind it, with the words "TROGDOR-CON" painted on it with pink.
The Cheat provided the $500 required to reserve the booth, presumably stealing it from Strong Sad (though Strong Bad rather unconvincingly denies he knows this).
While they were behind the booth selling gamertags, they encountered Strong Sad and Homestar Runner, who were both in costumes as they made their appearance. No exact location is known about the booth, only that is at a convention similar to "DragonCon".