Getz was born in the Detroit suburb of Southfield, Michigan, and was raised in Grosse Pointe, Michigan by Art and Betsy Getz. He attended Grosse Pointe South High School ('South'), where he was a 3 time All-Michigan selection in baseball and holds the South career records for batting average (.465), doubles, stolen bases, walks, and saves. Getz was a member of South's State Championship baseball team during his junior year. He shared the title of "Michigan's Mr. Baseball" in 2002 and also lettered in football and golf. Getz was drafted in the 6th round by the Chicago White Sox in 2002, but opted to play baseball at Wake Forest University where his father had attended college. Getz transferred to the University of Michigan to play baseball after just one season at Wake Forest. He holds the single season Big Ten records for at bats, hits, and was an All Big Ten Selection in 2004 and 2005.
Getz was again selected by the Chicago White Sox in the fourth round of the 2005 Amateur Draft. In 2005, he played 6 games for the Great Falls White Sox, the Sox rookie league affiliate before being promoted to the Single-A Kannapolis Intimidators where he played in 55 games. In 2006, Getz played in 130 games for the Double-A Birmingham Barons. Limited by injury, Getz played in just 72 games for Birmingham during the 2007 season, batting .299.
Getz was called up to the White Sox on August 9, 2008. He first appeared in a game against the Kansas City Royals three days later on August 12, where he recorded his first hit and RBI off Royals pitcher Josh Newman in his one and only at-bat during the 8th inning. The next day, he had his first Major League start, replacing Alexei Ramirez at second base. He went 1-3 with a single.