CONCORD, N.H. // A convicted tax evader who had holed up in his home for months after walking out of his federal trial arrived yesterday at a federal prison in Elkton, Ohio, authorities said. Supporters of Ed Brown and his wife, Elaine, had begun to question his whereabouts, noting he had been listed as not in custody of the Federal Bureau of Prisons. On at least one blog friendly to the Browns, supporters wondered whether he "disappeared into a black hole and is being mistreated or even tortured." Asked yesterday about the message, U.S. Marshal Stephen Monier dismissed it, saying, "That's absolutely ludicrous." Ed Brown, 65, had been staying at undisclosed locations under watch of marshal's deputies on his way to prison via the government prisoner transport system, Monier said.