Owners of the posh La Costa Resort Hotel and Spa in Carlsbad, a favorite of entertainment and sports celebrities, are negotiating with potential buyers, a resort official said. "We did not put a 'For Sale' sign out front," said Gerald Gleason, executive vice president of La Costa. "But we have talked to some people this year, and currently are talking with some that have a high degree of interest in us, and we have a high degree of interest in them." Gleason declined to disclose a selling price for the 600-acre resort in northern San Diego County, which includes two golf courses, a 482-room hotel, seven restaurants, tennis courts and a renowned spa. He also declined to disclose the names of potential buyers, although he confirmed negotiations have been held recently with a Japanese group that is reportedly also interested in purchasing a 1,000-acre resort in central Florida. One of the three owners of La Costa is Merv Adelson, head of Lorimar Telepictures Corp. Co-owners are Irwin Molasky, a Las Vegas real estate developer identified by Gleason as a member of Lorimar's board, and Allard Roen of Carlsbad, who has served as general managing partner of La Costa for about 20 years.