THE BUZZ – Karen Anderson of Orinda, Calif., wore a name tag identifying her as the Widow MacNamara from "The Valley of Fear." (Her California club takes its name, the Scowrers and the Molly Maguires, from that novella.) Her husband, Poul Anderson, the science fiction writer, said he often returned to the works of Sir Arthur Conan Doyle. Of his own writing, he said, "Oh, every once in a while, I smuggle in a reference."