Yes, you can also use the standard mileage method (there are two - standard and actual, you can choose which one you'd like to use) if you haven't use the actual method in the prior year.
If you are an employee and if the reimbursement is included in your gross wages - you can deduct the full amount. Otherwise, only the difference between reimbursed and unreimbursed amount is deductible.
If you are self-employed - only the unreimbursed amount is your deduction.