Hello John,
The sales tax Id is also called a Retail or Reseller's License, State Sales Tax Id, Tax Id, Resale Number, Resale Certificate, or Vendor's License.
* If you live in the USA or Canada. Most states have a sales tax, but there are a couple that don't. If you reside in one of these states just let the wholesaler know and they may have a different form or requirement for you to complete.
* If you sell online to make money (i.e. You sell more seriously than just getting rid of a few old things from around the house every now and then). You need a seller's permit so you can charge and collect taxes, which you'll pay to your state government later.
* If you want to purchase goods wholesale from a US supplier (and you are also based in the US), you need a seller's permit to buy wholesale sales tax free.
* If your business is a sole proprietorship with no employees, you can use your own Social Security number as your Taxpayer Identification Number, since the government doesn't draw any legal distinction between your business and your personal finances. If you have any other business structure or you have employees, you must get a separate Employer Identification Number from the IRS. (Sole proprietors without employees can also get an EIN if they choose.) The IRS allows you to apply for and receive an EIN in minutes online.
Hope this helps! :)