Never accuse the Los Angeles Times of having tabloid tastes. Buzz hears the paper has been receiving cryptic letters from the accused killer of actress Rebecca Schaeffer (“My Sister Sam”), but didn’t deem them newsworthy. After the Times reviewed “The End of Innocence,” a Skouras film which co-starred Schaeffer, the critic began receiving letters from Robert Bardo, an obsessive fan charged with the murder. The letters, say sources, include cryptic statements about the crime. Portland Oregonian reporter Dave Austin, who has covered the case since Schaeffer was killed on July 18,1989 (Schaeffer grew up in Portland), said he heard about the letters and tried to get copies and clips. He was told the Times didn’t publish them, and the paper refused to let him see the letters. A Times spokeswoman said the letters weren’t published because they “didn’t add anything to the story.” The letters were turned over to the D.A.’s office.