Klebba was an occasional guest on The Howard Stern Show in the 1990s, and was given the nickname "Marty the Midget".
Klebba starred as Friday, one of the seven dwarfs, in the 2001 made-for-TV film Snow White: The Fairest of Them All. In 2003, Klebba starred as Hank Dingo in the Comedy Central made-for-TV movie Knee High P.I.. He also made an appearance as a demon in the Charmed, season 6 episode Witch Wars (2004). He has also appeared in iCarly and Drake & Josh as Nug Nug.
Klebba has acted in various productions, most notably the Pirates of the Caribbean series, as Marty, one of Captain Jack Sparrow's Black Pearl crew, in films one through three, and five. In 2003, he played the ring announcer in the Cradle 2 the Grave. In 2009, Klebba played the role of "Count Le Petite" in All's Faire in Love, a romantic comedy set at a Renaissance fair. He has also been in low budget horror/comedy films Feast 2: Sloppy Seconds & Feast III: The Happy Finish as "Thunder."
Klebba made many appearances as Randall Winston in the television series Scrubs. He starred in the CSI: Crime Scene Investigation episode "The Chick Chop Flick Shop" (2007) as Dickie Jones, and in the CSI: NY episode "Uncertainty Rules" (2010) as Calvin Moore. Also in 2010, Klebba guest starred as Hibachi in Pair of Kings, a Disney TV series. He played Todd Moore in the Bones (TV series) season 5 episode "Dwarf in the Dirt"' (2010).
In 2011, Klebba appeared on The Cape as a series regular named "Rollo". He also appeared once again in Mirror Mirror (2012), which starred Julia Roberts, Armie Hammer (The Social Network), and Lily Collins.
