If you are an Uber driver you can deduct your car expenses in one of two ways - either a flat rate per mile driven (currently 53.5 cents per mile), or deduct actual expenses. You can't do both. If you choose to deduct actual expenses, insurance is line 15 on Schedule C. If you take the flat rate, you do not include it anywhere.
EDIT: If you want to deduct insurance on a vehicle when deducting actual vehicle expenses, they are included on Line 9 of Schedule C, not Line 15. You enter all your vehicle expenses on the Car and Truck Expenses Worksheet, and totals are carried over to Line 9. My mistake.
