If you want to be a profitable reseller, you will be dealing with a lot of wholesale companies and these most, if not all, wholesalers require a sales tax number from you. If you think you can get away without this, then you are not planning to be a great eBay seller in the long run.

You can get a hold of this by contacting your sales tax authority in your designated state or county. Calling your local chamber of commerce should be a good start in getting the appropriate information that will ultimately land you your sales tax number.