This was over the radio live, so there is no specific link on KABC 790 LA..
Here is your link:
FBI - Media Advisory: Press Briefing
FBI Boston April 18, 2013
Special Agent Greg Comcowich (617) 223-6110
Special Agent in Charge of the FBI’s Boston Field Office Richard DesLauriers, United States Attorney Carmen Ortiz, and FBI JTTF law enforcement partners will hold a press briefing today, April 18, regarding the Boston Marathon investigation, at 5:00 p.m. at The Sheraton Hotel, 39 Dalton Street, Third Floor, Commonwealth Ballroom, Boston.
Valid media credentials are required for admittance.