Legal Question in Business Law in Ohio

Yes, you can purchase "plain" clothing to decorate and sell - think of the companies who put corporate logos on golf shirts. There are suppliers out there who provide the clothing in bulk amounts at wholesale prices that might be beneficial for you.

You might also want to look into whether you are eligible for a tax exemption. Because you would be buying the clothing to then sell to customers, you may be able to avoid paying taxes on the clothing when you buy it. An accountant or tax attorney should be able to help.