Veronica's (Kristen Bell) line, "Hey! Careful, man, there's a beverage here!" is another of many references in the series to the movie, The Big Lebowski (1998).
When Veronica (Kristen Bell) opens the door to Logan (Jason Dohring) he asks, "Were you expecting Sidney Poitier?" Sidney Poitier is the father of Sydney Tamiia Poitier, who played Mallory Dent in season one.
Enrico Colantoni (Keith) appeared in Just Shoot Me! (1997) with Laura San Giacomo (Harmony Chase) who appears in 3 episodes of Veronica Mars.
Keith is confronted to have posed as Adrian Monk. Adrian Monk, played by Tony Shalhoub, is the main character of the TV show Monk (2002). Adrian Monk, much like Keith, is a former detective who is now working as a private investigator. Furthermore Enrico Colantoni (Keith) had a one episode guest role on Monk.
The title of this episode references a line spoken in the film Apocalypse Now (1979) by Colonel Kilgore, the "Charlie" in question being the Viet Cong. "Charlie Don't Surf" is also the title of a song from The Clash's album, "Sandinista!".