Berdych had few problems with Berlocq, winning 6-3, 6-3, 6-4 to give the Czechs an insurmountable 3-1 lead in the semifinal. Berlocq filled in for Juan Martin del Potro, who missed the decisive reverse singles with a left wrist injury.
The Czechs return to the final for the second time in four seasons and will host it in November. They will have a chance to avenge the 2009 final defeat to Spain.
"This is going to be the highlight of my career up until now," Berdych said of facing Spain. "It is going to be very difficult playing against Spain, the champion, but at least we are lucky to be playing at home."
Del Potro, the 2009 U.S. Open champion, defeated Radek Stepanek on Friday but was ruled out for Sunday by the Argentina team doctor, who said the match made his injury worse. Del Potro has a history of wrist injuries.
Argentina was trying to reach its fifth Davis Cup final. It has lost all four, including last year against Spain.
There wasn't enough firepower with del Potro absent and David Nalbandian -- the team leader for several years -- sidelined with an abdominal injury.
Argentina's chances faded quickly Saturday. The loss in doubles to Berdych and Stepanek was followed by del Potro's withdrawal, leaving only Berlocq -- who has never won an ATP event -- to face No. 6-ranked Berdych. Even Diego Maradona, cheering in the stands for the third straight day, could not inspire Berlocq on the red outdoor clay at Parque Roca.
Berdych won all three points for the Czechs. He beat Juan Monaco on Friday 6-1, 4-6, 1-6, 6-4, 6-4, then teamed with Stepanek for a three-set win in doubles to set up his clincher Sunday.
It was Berlocq's Davis Cup debut in singles after losing Saturday in doubles with Eduardo Schwank.
Federer clinches Swiss victory in World Group
The world's top-ranked player was rarely troubled by the 50th-ranked Haase on the temporary clay court in Amsterdam as he comfortably sealed victory and his team's return to the World Group next year.
Federer and Wawrinka won their opening singles Friday and lost in doubles Saturday to Haase and Jean-Julien Rojer.
Bhupathi, Bopanna barred from India's team
NEW DELHI -- The All India Tennis Association says it will not consider veterans Mahesh Bhupathi and Rohan Bopanna for Davis Cup for two years after both refused to partner with Leander Paes in doubles at the London Olympics.
The association said in a statement Sunday it had "decided not to consider" Bhupathi and Bopanna for selection until June 30, 2014. Bhupathi has been a Davis Cup player since 1995 and Bopanna for 10 years.
Both players were dropped from the squad for a relegation playoff matchup against New Zealand in which a second-string India team completed a 5-0 victory in Chandigarh on Sunday.
Information from The Associated Press was used in this report.