SeaWorld and Busch Gardens are getting in on holiday shopping with buy one, get one free ticket deals worth up to $180 in an online-only sale. First, you have to register for the parks' email updates at seaworldorlando.com or at buschgardenstampa.com. Then at 12:01 a.m. on Friday through Dec. 1, details on the deals will be sent to email subscribers. SeaWorld's "Blue Friday" will have buy one, get one deals for tickets and annual passes, as well as in-park experiences such as its dolphin tour. Busch Gardens says it will have also have BOGO specials, merchandise discounts and park experiences. — Sharon Kennedy Wynne, Times staff writer