In this episode, Dean and Sam have the surnames Smith and Wesson, respectively. Like the characters' actual surname, Winchester, the name Smith & Wesson is the name of a famous gun manufacturing company.
Dean Smith's family members' names are - dad: Bob (a.k.a. Bobby Singer), Mom: Ellen (a.k.a. Ellen Harvelle), and sister: Jo (a.k.a. Jo Harvelle). Sam Wesson's fiancée's name is Madison (a.k.a. Madison Owens).
Around 2:20 Dean says "Alright tell me one more time. You said lemon and, what was it, cayenne, and maple syrup? Are you serious? How much did you lose?" - This is a reference to a controversial diet/cleanse called The Master Cleanse
Actual "Ghostfacers" webisodes (Ghostfacers (2010)) were created to accompany this season. In the first one, shots of their workshop reveal a dart board with the Winchesters' pictures on it. If "Dean Smith" and "Sam Wesson" had watched all the Ghostfacers' online instructional videos, they likely would've seen those photos.
Dean, "How creative". Zachariah, "You should see my decoupage". Dean, "Gross". Decoupage is an arts and crafts where you glue bits of colored paper, leaves, snatches of fabric, etc. to something for decorative purposes. Decolletage, which is what Dean was thinking, is breast cleavage or the low neckline that reveals cleavage.