More than a billion barrels of oil could be available to drill beginning next year. The Interior Department is preparing to sell five leases that would give oil companies the right to drill in a 95-million-acre area in the western and central Gulf off the coasts of Texas, Louisiana, Mississippi and Alabama. Offshore drilling has been put on hold since the BP oil spill last year. Officials say the leases could yield more than a billion barrels of oil between 2012 and 2017.