eBay Mileage Deduction

As an eBay seller, I understand that I can claim the mileage used for trips to the post office, UPS, etc.  I do keep track of my mileage in a log book. My question is how do I have to categorize the standard mileage deduction?  I believe the standard mileage rate is $0.67 per mile. Should it be classified under miscellaneous as "transportation expense" or does it have to be classified under "car and truck expenses" on schedule C where you have to input the information about your vehicle? I don't have a "business" vehicle. I use my vehicle for both personal and for taking packages to the carriers. My mileage log only consists of the trips to the carriers and places to buy merchandise pertaining to selling on eBay. I just want to make sure of how and where on the form to report the mileage.