I have a Canadian company where (online) they hire me to design websites for their business (American businesses). They pay in Canadian dollars for this website. What I am interested in is taxes or permit or licenses, if the American customers use my services. Or would this just be classified as a purchase of a product?
This is being classified as them purchasing a service in Canada which to them would be an expense and to you would be most likely classified as income. Since you are not hosting their website in the US you are not responsible for getting anything for it your customer is. For Canada unless there is an export control on website design (never say never) you are not responsible for permits either as long as your customer is not a Drug Cartel or something similar.