The fact that it was for your job as an employee makes it more complicated. If your employer required you to drive to a location to pick up the item and you were not reimbursed for the mileage then it may be deductible as an unreimbursed employee expense (Form 2106). Expenses include on Form 2106 are then reported on Schedule A (Itemized Deductions), limited by 2% of your AGI. So, unless you are already itemizing deductions, including the mileage may not produce a tax benefit.
