Charging tax when selling online

  I have an online business and I know I need to charge OH tax to people that have bought from me online and are having their item shipped to an OH address. My question is when I have someone from OH that has a tax exemption #, do I have to have them fax or send me documentation of their state tax exemption #. I just had this asked of me when I purchased something from an OH seller on Ebay. I have always given my tax # to other OH sellers online and at Antique shows. But I have never had to produce the paper showing it and give them a copy. Is this something people are suppose to be doing and are lax about? This women insisted it is the law. I told her she could ship the item to my WV address and then she wouldn't need me to fax my info. She said she would still have to charge me the tax since it was bought in OH. Now that is CRAZY, right? It was bought online and being shipped to the buyers address. What is wrong with people? If anyone knows the legal answer to online sales tax, including people that are exempt/re-selling the item they bought with a tax # given to sell, please, please let me know. I greatly appreciate any help that can be given.

  Everyone please have a Wonderful Day !